3 different Alexa modules, which one is the best?

[romain]

@borrigan Hello. I end up successfully setting MMM-AlexaPi and MMM-alexa.
they both have adventages and inconvinient
-MMM-AlexaPi

• This module isn’t a stand alone module. You need to install AlexaPi on you pi ( https://github.com/alexa-pi/AlexaPi )
• This module is ONLY to show the status of AlexaPi. And this is AlexaPi that allow you to talk to Alexa. Meaning you don’t need the mirror at all to use it. But it’s neat because you can “see” what’s happening. Also Alexa saying “yes” when you say her name.
• It might or might not be easy to setting up. Some people won’t have any issue using it by following the setup instruction and other would have to tweaks some things.
• slower than MMM-alexa

-MMM-alexa

• It is a stand alone module. Meaning you just need this module to talk to Alexa.
• The square indicate you the status . yellow is bad configuration if I recall correctly. Red is ready to listen. green is listening.
• It is not activated by voice. You need either a button or to send the right notification to the module to make Alexa listen to you.
• It seem to not answer as much as MMM-AlexaPi
• You need to add https://sakirtemel.github.io/MMM-alexa/ to the allow return URL in your avs security settings of your device . And need to generate the first token by going in that first url and enter the requested information
• faster than MMM-AlexaPi

in both case I had to tweak some of my sound configurations files so my microphone is picked up and the output is my speaker.
Because MMM-Alexa needed to be activated manually or by another module (and the fact it seem to provide less answer) I think MMM-AlexaPi is better. Even though AlexaPi seem a bit slower to answer. To trigger MMM-Alexa I used the voicecontrol module (it’s a module that convert voice into notification. I set up the word “Alexa” to send the right notification to mmm-alexa) but the voicecontrol module seem to have a loooooooooot of false positive. It was activated way to much even if I didn’t talk sometime.

I didn’t successfully made mirrormirroronthewall worked though (I might try again later. I didn’t tryed since I made the other two works)
I think mirrormirroronthewall is probably the best module of all three since is suppositivly allow you to do more than the other two that only allow you to ask question to alexa and get answers from it.

as for the

But it does not say how to develop this module :(

You can either use an already existing moduel like “voicecontrol” to do that.

or developping something yourself. to do that:
You can for example take as a template the helloworld module in the ~/MagicMirror/modules/default as a template . copy/past it in the ~/MagicMirror/modules , rename the folder to something else. let’s say “toto” as an example, then rename the file inside it to match that name. helloworld.js should now be toto.js . now open the toto.js and replace all the hello words by toto.
Then delete the text: "Hello World!" and the wrapper.innerHTML = this.config.text; since you don’t need to display anything.
Now you can write this.sendNotification('ALEXA_START_RECORDING', {}); where was the wrapper.innerHTML = this.config.text;
And that send the notification to start recording what you are saying to mmm-alexa. However that example will only work once.

If you never code something before, I don’t recomand you to do the developping of a module like this yourself. It’s better to use an already existing module.

/!\ if your sound configuration isn’t good, you might not be able to use voicecontrol and mmm-alexa in the same time.
Explaining the sound configuration here would be pointless since you might not have those issue.

[borrigan]

Thank you very very much @romain ! I will go for AlexaPi with MMM-AlexaPi. I spent all yesterday trying to set it up, and I will continue today, your input is very valuable. Just a few newbie, extra questions:

• AlexaPi service, when running, is “Always On”? It is always listening? How to test it directly without having integrated with MMM-AlexaPi Yet?

• Where can the activation word be configured? If I just say “Alexa”, should it work?

• Finally, I spent hours troubleshooting the microphone. It is a very standard Logitech Microphone. I just could not get it working.

Here are:

Result from >lsusb command:

pi@raspberrypi:~ $ lsusb
Bus 001 Device 006: ID 17ef:6019 Lenovo
Bus 001 Device 005: ID 04b3:3025 IBM Corp. NetVista Full Width Keyboard
Bus 001 Device 004: ID 046d:0a03 Logitech, Inc. Logitech USB Microphone
Bus 001 Device 003: ID 0424:ec00 Standard Microsystems Corp. SMSC9512/9514 Fast Ethernet Adapter
Bus 001 Device 002: ID 0424:9514 Standard Microsystems Corp.
Bus 001 Device 001: ID 1d6b:0002 Linux Foundation 2.0 root hub

result from the > arecord -L command:

pi@raspberrypi:~ $ arecord -L
null
Discard all samples (playback) or generate zero samples (capture)
pulse
PulseAudio Sound Server
sysdefault:CARD=Microphone
Logitech USB Microphone, USB Audio
Default Audio Device
front:CARD=Microphone,DEV=0
Logitech USB Microphone, USB Audio
Front speakers
surround21:CARD=Microphone,DEV=0
Logitech USB Microphone, USB Audio
2.1 Surround output to Front and Subwoofer speakers
surround40:CARD=Microphone,DEV=0
Logitech USB Microphone, USB Audio
4.0 Surround output to Front and Rear speakers
surround41:CARD=Microphone,DEV=0
Logitech USB Microphone, USB Audio
4.1 Surround output to Front, Rear and Subwoofer speakers
surround50:CARD=Microphone,DEV=0
Logitech USB Microphone, USB Audio
5.0 Surround output to Front, Center and Rear speakers
surround51:CARD=Microphone,DEV=0
Logitech USB Microphone, USB Audio
5.1 Surround output to Front, Center, Rear and Subwoofer speakers
surround71:CARD=Microphone,DEV=0
Logitech USB Microphone, USB Audio
7.1 Surround output to Front, Center, Side, Rear and Woofer speakers
iec958:CARD=Microphone,DEV=0
Logitech USB Microphone, USB Audio
IEC958 (S/PDIF) Digital Audio Output
dmix:CARD=Microphone,DEV=0
Logitech USB Microphone, USB Audio
Direct sample mixing device
dsnoop:CARD=Microphone,DEV=0
Logitech USB Microphone, USB Audio
Direct sample snooping device
hw:CARD=Microphone,DEV=0
Logitech USB Microphone, USB Audio
Direct hardware device without any conversions
plughw:CARD=Microphone,DEV=0
Logitech USB Microphone, USB Audio
Hardware device with all software conversions

Log from AlexaPi

● AlexaPi.service - Alexa client for all your devices
Loaded: loaded (/usr/lib/systemd/system/AlexaPi.service; enabled)
Active: active (running) since Mon 2017-04-24 10:59:14 CDT; 7s ago
Docs: https://github.com/alexa-pi/AlexaPi/wiki
Main PID: 1626 (python)
CGroup: /system.slice/AlexaPi.service
├─1626 /usr/bin/python /opt/AlexaPi/src/main.py --daemon
├─1638 /usr/bin/pulseaudio --start --log-target=syslog
└─1657 sox -q /opt/AlexaPi/src/resources/hello.mp3 -t alsa default vol -6 dB pad 0 0

Apr 24 10:59:20 raspberrypi pulseaudio[1638]: [pulseaudio] module-udev-detect.c: Tried to configure /devices… 10s
Apr 24 10:59:21 raspberrypi python[1626]: Exception in thread Thread-1:
Apr 24 10:59:21 raspberrypi python[1626]: Traceback (most recent call last):
Apr 24 10:59:21 raspberrypi python[1626]: File “/usr/lib/python2.7/threading.py”, line 810, in __bootstrap_inner
Apr 24 10:59:21 raspberrypi python[1626]: self.run()
Apr 24 10:59:21 raspberrypi python[1626]: File “/usr/lib/python2.7/threading.py”, line 763, in run
Apr 24 10:59:21 raspberrypi python[1626]: self.__target(*self.__args, **self.__kwargs)
Apr 24 10:59:21 raspberrypi python[1626]: File “/opt/AlexaPi/src/alexapi/triggers/pocketsphinxtrigger.py”, …hread
Apr 24 10:59:21 raspberrypi python[1626]: inp = alsaaudio.PCM(alsaaudio.PCM_CAPTURE, alsaaudio.PCM_NORMAL, …ce’])
Apr 24 10:59:21 raspberrypi python[1626]: ALSAAudioError: Input/output error [front:CARD=Microphone,DEV=0]
Hint: Some lines were ellipsized, use -l to show in full.

Thank you so much for your help, I don’t mean to take too much from your time but I am really frustrated :(

Gerardo
Mexico City

[romain]

@borrigan

AlexaPi service, when running, is “Always On”? It is always listening? How to test it directly without having integrated with MMM-AlexaPi Yet?

you should hear “hello” when it start and then if you say Alexa you should hear “yes” then you can ask a question. It is always listening.
A little tips for you, before using the service, try to run AlexaPi yourself. It provide you more debugging info that way.
To do it, first desactivate the service with the terminal by writing sudo systemctl stop AlexaPi.service; sudo systemctl disable AlexaPi.service (you can reactivate later by doing sudo systemctl enable AlexaPi.service).
Then you can run AlexaPi yourself by writing in the terminal /opt/AlexaPi/src/main.py -d (If you you putted it on that location anyway).

Where can the activation word be configured? If I just say “Alexa”, should it work?

in the yaml file in /etc/opt/AlexaPi/config.yaml there is a section pocketsphinx: (this is what is use to detect words I believe). in that section you have a key phrase: with "alexa" as a value. you can simply change the word to another word. Do not choose an over complicated one though, I think pocketsphinx try to guess what it supposed to sound like based on the spelling so if you choose a word not in English it might not guess correctly. You shoudl let alexa untill you get it to work though, because we know that one work for sure. You can test other word later.

Finally, I spent hours troubleshooting the microphone. It is a very standard Logitech Microphone. I just could not get it working.

I am no expert in sound but I going to try to help you.
First, I rather have the output from arecord -l rather than arecord -L . the later give to much information to my understanding.
The output of my arecord -l look like this:

pi@raspberrypi:~ $ arecord -l
**** List of CAPTURE Hardware Devices ****
card 1: Device [USB Audio Device], device 0: USB Audio [USB Audio]
  Subdevices: 1/1
  Subdevice #0: subdevice #0

I can see it’s “card 1” and “device 0” . that’s what I am interesting about.
then, my aplay -l give me

pi@raspberrypi:~ $ aplay -l
**** List of PLAYBACK Hardware Devices ****
card 0: ALSA [bcm2835 ALSA], device 0: bcm2835 ALSA [bcm2835 ALSA]
  Subdevices: 8/8
  Subdevice #0: subdevice #0
  Subdevice #1: subdevice #1
  Subdevice #2: subdevice #2
  Subdevice #3: subdevice #3
  Subdevice #4: subdevice #4
  Subdevice #5: subdevice #5
  Subdevice #6: subdevice #6
  Subdevice #7: subdevice #7
card 0: ALSA [bcm2835 ALSA], device 1: bcm2835 ALSA [bcm2835 IEC958/HDMI]
  Subdevices: 1/1
  Subdevice #0: subdevice #0
card 1: Device [USB Audio Device], device 0: USB Audio [USB Audio]
  Subdevices: 1/1
  Subdevice #0: subdevice #0

I using the default speaker output, which is the bcm2835 Alsa device which is “card 0” and “device 0”

Knowing that you can test if your device working by doing the following:
meaning you should be able to do a aplay -D hw:0,0 /usr/share/sounds/alsa/Front_Center.wav to test your speaker where “hw:0,0” (you could also put “plughw:0,0”) is your output device. Not sur what does “hw” and “plughw” mean, but the numbers are the card number and the device number. 0,0 in my example (remember the aplay -l above)
this will use the vlc handler i beleive. You can test it the same way with play instead of aplay for the sox handler.

you can test your michrophone in the same way by doing arecord -r 48000 -f S16_LE -D hw:1,0 -d 5 test.wav this will tell to record with the device hw:1,0 (in my example the card 1, device 0) for 5 second at a rate of 48000Hz and as S16_Le type (not sure what that is) and the result will be put in a file name test.wav. You can then play or aplay that file to see if the recording whent well.

If you manage to make those command work. In the /etc/opt/AlexaPi/config.yaml there is a section sound: with a key “input_device:” and a key “output_device:” . Both of those key have for value “default” . for the output it’s easy, the default is the system defautl output which is hw:0,0 in my example. so you can let default or put “hw:0,0” instead if you want to use that output like me.
The tricky part is the input. The input is your michrophone, but there is no “default” michrophone in the pi right ? so the chance AlexaPi understand what you are talking about are prett slim in my opinion.
But when I wrote “hw:1,0” or “plugwh:1,0” instead of default , I had an error. For some reason it didn’t wanted to take that value. That’s when trickery was needed for me. I’m sure some people hadn’t to do that but I did.
I creat a alsa configuration file name “asound.conf” with the following in it :

pcm.myTest {
    type dsnoop
    ipc_key 816357492
    ipc_key_add_uid 0
    ipc_perm 0666
    slave {
        pcm "hw:1,0"
        channels 1
    }
}

pcm.!default {
        type asym
        playback.pcm {
                type plug
                slave.pcm "hw:0,0"
        }
        capture.pcm {
                type plug
                slave.pcm "myTest"
        }
}

This overrite what is the “default” configuration.
type asym mean my playback and default arn’t on the same sound device.
the playback.pcm describe what is my output device. In my example you can see i putted “hw:0,0” because I use the default output.
the capture.pcm describe the input device (microphone). I put “MyTest” as a name which is describe above in the file (the name isn’t very explicit but I was testing and never changed it >.> )
I am not going to enter in the detail for the myTest thing, but basically, it’s tell that the michrophone can be use in multiple application at the time and that it is the “hw:1,0” (remember the arecord -l thing above in the post)

This asound.conf file should be put in the /etc/ folder.

Well. That’s it. That’s what I had to do to make my microphone work for AlexaPi. Adapt this to your own devices and it might work like me.
Remember to test it whitout the service first and when that’s work you activate the service and see if it still work or not. and if not we’ll try to understand why.

[johnnyboy]

This post is deleted!

[borrigan]

@romain thank you very very much for all this feedback. I was definitely missing some pieces of the puzzle. I will try this again today and post my findings here. Have a great day!

[romain]

@johnnyboy I struggle because of this @johnnyboy at first. But the lambda service is working both with us and ireland (west-eu or eu-west. don’t remember exactly now).
I end up have skill that was working. On the amazon interfaces anyway by choosing that instead of us. (even though I’m in france. I had no error anymore on the amazon test aera)
I had to change the hard coded region in the code though (easy fix).
I think I had no more error at the end (don’t remember for sure). But nothing was happening when I talked (maybe it was again a microphone issue. Not really sure about that)
I also did not understood how to use the npm start dev correctly at that time so maybe I would be able to do a better job at finding the issue now.
Maybe I try today, maybe I never try again. we’ll see (it’s not my raspberry pie I using so I am limited in when I can use it. So I rather do what I am ask to first before trying again)

[johnnyboy]

This post is deleted!

[romain]

@johnnyboy Yes, But it’s not your fault. I have read an entire very long thread about mirror mirror on the wall (and maybe some others, I don’t remember if all the information were on the same spot or not) and it seem that one guy talked about trying that (changing the region) and the creator of the module himself didn’t knew Ireland was possible. But he did point out in which file the region thing was. (it wasn’t had to find though).
So I do think he meant that “that one ‘must’ be in the us-east” because he didn’t knew there was another option.
And he didn’t changed his tutorial to reflect that. (I’m guessing because he wasn’t able to test this way itself. Or maybe he wasn’t willing to)

[borrigan]

@romain hi again!!

I have done some progress. I followed your instructions, created the asound.conf file and setup myTest as the input device in the config.yaml file. When I run alexaPi, now it does not give me a microphone error, but a strange “Capture data too large” error. I get to hear the “hello” sound but when I speak “alexa” it won’t do anything.

Really weird. Here is the full output of main.py execution:

pi@raspberrypi:/opt/AlexaPi/src $ /opt/AlexaPi/src/main.py -d
INFO: pocketsphinx.c(152): Parsed model-specific feature parameters from /usr/local/lib/python2.7/dist-packages/pocketsphinx/model/en-us/feat.params
Current configuration:
[NAME]			[DEFLT]		[VALUE]
-agc			none		none
-agcthresh		2.0		2.000000e+00
-allphone				
-allphone_ci		no		no
-alpha			0.97		9.700000e-01
-ascale			20.0		2.000000e+01
-aw			1		1
-backtrace		no		no
-beam			1e-48		1.000000e-48
-bestpath		yes		yes
-bestpathlw		9.5		9.500000e+00
-ceplen			13		13
-cmn			live		batch
-cmninit		40,3,-1		41.00,-5.29,-0.12,5.09,2.48,-4.07,-1.37,-1.78,-5.08,-2.05,-6.45,-1.42,1.17
-compallsen		no		no
-debug					0
-dict					/usr/local/lib/python2.7/dist-packages/pocketsphinx/model/cmudict-en-us.dict
-dictcase		no		no
-dither			no		no
-doublebw		no		no
-ds			1		1
-fdict					
-feat			1s_c_d_dd	1s_c_d_dd
-featparams				
-fillprob		1e-8		1.000000e-08
-frate			100		100
-fsg					
-fsgusealtpron		yes		yes
-fsgusefiller		yes		yes
-fwdflat		yes		yes
-fwdflatbeam		1e-64		1.000000e-64
-fwdflatefwid		4		4
-fwdflatlw		8.5		8.500000e+00
-fwdflatsfwin		25		25
-fwdflatwbeam		7e-29		7.000000e-29
-fwdtree		yes		yes
-hmm					/usr/local/lib/python2.7/dist-packages/pocketsphinx/model/en-us
-input_endian		little		little
-jsgf					
-keyphrase				alexa
-kws					
-kws_delay		10		10
-kws_plp		1e-1		1.000000e-01
-kws_threshold		1		1.000000e-10
-latsize		5000		5000
-lda					
-ldadim			0		0
-lifter			0		22
-lm					
-lmctl					
-lmname					
-logbase		1.0001		1.000100e+00
-logfn					
-logspec		no		no
-lowerf			133.33334	1.300000e+02
-lpbeam			1e-40		1.000000e-40
-lponlybeam		7e-29		7.000000e-29
-lw			6.5		6.500000e+00
-maxhmmpf		30000		30000
-maxwpf			-1		-1
-mdef					
-mean					
-mfclogdir				
-min_endfr		0		0
-mixw					
-mixwfloor		0.0000001	1.000000e-07
-mllr					
-mmap			yes		yes
-ncep			13		13
-nfft			512		512
-nfilt			40		25
-nwpen			1.0		1.000000e+00
-pbeam			1e-48		1.000000e-48
-pip			1.0		1.000000e+00
-pl_beam		1e-10		1.000000e-10
-pl_pbeam		1e-10		1.000000e-10
-pl_pip			1.0		1.000000e+00
-pl_weight		3.0		3.000000e+00
-pl_window		5		5
-rawlogdir				
-remove_dc		no		no
-remove_noise		yes		yes
-remove_silence		yes		yes
-round_filters		yes		yes
-samprate		16000		1.600000e+04
-seed			-1		-1
-sendump				
-senlogdir				
-senmgau				
-silprob		0.005		5.000000e-03
-smoothspec		no		no
-svspec					0-12/13-25/26-38
-tmat					
-tmatfloor		0.0001		1.000000e-04
-topn			4		4
-topn_beam		0		0
-toprule				
-transform		legacy		dct
-unit_area		yes		yes
-upperf			6855.4976	6.800000e+03
-uw			1.0		1.000000e+00
-vad_postspeech		50		50
-vad_prespeech		20		20
-vad_startspeech	10		10
-vad_threshold		2.0		2.000000e+00
-var					
-varfloor		0.0001		1.000000e-04
-varnorm		no		no
-verbose		no		no
-warp_params				
-warp_type		inverse_linear	inverse_linear
-wbeam			7e-29		7.000000e-29
-wip			0.65		6.500000e-01
-wlen			0.025625	2.562500e-02

INFO: feat.c(715): Initializing feature stream to type: '1s_c_d_dd', ceplen=13, CMN='batch', VARNORM='no', AGC='none'
INFO: acmod.c(166): Using subvector specification 0-12/13-25/26-38
INFO: mdef.c(518): Reading model definition: /usr/local/lib/python2.7/dist-packages/pocketsphinx/model/en-us/mdef
INFO: mdef.c(531): Found byte-order mark BMDF, assuming this is a binary mdef file
INFO: bin_mdef.c(336): Reading binary model definition: /usr/local/lib/python2.7/dist-packages/pocketsphinx/model/en-us/mdef
INFO: bin_mdef.c(516): 42 CI-phone, 137053 CD-phone, 3 emitstate/phone, 126 CI-sen, 5126 Sen, 29324 Sen-Seq
INFO: tmat.c(149): Reading HMM transition probability matrices: /usr/local/lib/python2.7/dist-packages/pocketsphinx/model/en-us/transition_matrices
INFO: acmod.c(117): Attempting to use PTM computation module
INFO: ms_gauden.c(127): Reading mixture gaussian parameter: /usr/local/lib/python2.7/dist-packages/pocketsphinx/model/en-us/means
INFO: ms_gauden.c(242): 42 codebook, 3 feature, size: 
INFO: ms_gauden.c(244):  128x13
INFO: ms_gauden.c(244):  128x13
INFO: ms_gauden.c(244):  128x13
INFO: ms_gauden.c(127): Reading mixture gaussian parameter: /usr/local/lib/python2.7/dist-packages/pocketsphinx/model/en-us/variances
INFO: ms_gauden.c(242): 42 codebook, 3 feature, size: 
INFO: ms_gauden.c(244):  128x13
INFO: ms_gauden.c(244):  128x13
INFO: ms_gauden.c(244):  128x13
INFO: ms_gauden.c(304): 222 variance values floored
INFO: ptm_mgau.c(476): Loading senones from dump file /usr/local/lib/python2.7/dist-packages/pocketsphinx/model/en-us/sendump
INFO: ptm_mgau.c(500): BEGIN FILE FORMAT DESCRIPTION
INFO: ptm_mgau.c(563): Rows: 128, Columns: 5126
INFO: ptm_mgau.c(595): Using memory-mapped I/O for senones
INFO: ptm_mgau.c(838): Maximum top-N: 4
INFO: phone_loop_search.c(114): State beam -225 Phone exit beam -225 Insertion penalty 0
INFO: dict.c(320): Allocating 138824 * 20 bytes (2711 KiB) for word entries
INFO: dict.c(333): Reading main dictionary: /usr/local/lib/python2.7/dist-packages/pocketsphinx/model/cmudict-en-us.dict
INFO: dict.c(213): Dictionary size 134723, allocated 1016 KiB for strings, 1679 KiB for phones
INFO: dict.c(336): 134723 words read
INFO: dict.c(358): Reading filler dictionary: /usr/local/lib/python2.7/dist-packages/pocketsphinx/model/en-us/noisedict
INFO: dict.c(213): Dictionary size 134728, allocated 0 KiB for strings, 0 KiB for phones
INFO: dict.c(361): 5 words read
INFO: dict2pid.c(396): Building PID tables for dictionary
INFO: dict2pid.c(406): Allocating 42^3 * 2 bytes (144 KiB) for word-initial triphones
INFO: dict2pid.c(132): Allocated 21336 bytes (20 KiB) for word-final triphones
INFO: dict2pid.c(196): Allocated 21336 bytes (20 KiB) for single-phone word triphones
INFO: kws_search.c(406): KWS(beam: -1080, plp: -23, default threshold -225, delay 10)
2017-04-26 19:58:32 DEBUG: Setting up playback handler: SoxHandler
2017-04-26 19:58:32 INFO: Checking Internet Connection ...
2017-04-26 19:58:32 DEBUG: Starting new HTTPS connection (1): api.amazon.com
2017-04-26 19:58:33 DEBUG: https://api.amazon.com:443 "GET /auth/o2/token HTTP/1.1" 404 29
2017-04-26 19:58:33 INFO: Connection OK
2017-04-26 19:58:33 INFO: AVS token: Requesting a new one
2017-04-26 19:58:33 DEBUG: Starting new HTTPS connection (1): api.amazon.com
2017-04-26 19:58:34 DEBUG: https://api.amazon.com:443 "POST /auth/o2/token HTTP/1.1" 200 980
2017-04-26 19:58:34 INFO: AVS token: Obtained successfully
2017-04-26 19:58:34 DEBUG: Stopping audio play
2017-04-26 19:58:34 DEBUG: Stopped play. No SoX process to stop
2017-04-26 19:58:34 DEBUG: Playing audio: /opt/AlexaPi/src/resources/hello.mp3
Exception in thread Thread-1:
Traceback (most recent call last):
  File "/usr/lib/python2.7/threading.py", line 810, in __bootstrap_inner
    self.run()
  File "/usr/lib/python2.7/threading.py", line 763, in run
    self.__target(*self.__args, **self.__kwargs)
  File "/opt/AlexaPi/src/alexapi/triggers/pocketsphinxtrigger.py", line 70, in thread
    _, buf = inp.read()
ALSAAudioError: Capture data too large. Try decreasing period size

2017-04-26 19:58:34 DEBUG: Started play. sox -q /opt/AlexaPi/src/resources/hello.mp3 -t alsa default vol -6 dB pad 0 0
2017-04-26 19:58:36 DEBUG: Finished play. 

Thank you very much for your patience @romain

Best regards,

Gerardo

[romain]

@borrigan Try to let “default” as an input device rather than myTest. The default thing will be in charge to call myTest itself (I think putting myTest directly doesn’t work for some weird reason I don’t now about)
Do you hear the “hello” when you run the script ?
If you still have the error after using the default, then ty to change you input handler from sox to vlc.I don’t think that’s related but at this point trying stuff might be the right thing x) Maybe that will fix it.