platform:
raspberrypi 4 , latest buster with all latest updateds

** steps to reproduce**
.config.js

/* Magic Mirror Config Sample
 *
 * By Michael Teeuw  http://michaelteeuw.nl
 * MIT Licensed.
 *
 * For more information how you can configurate this file
 * See https://github.com/MichMich/MagicMirror#configuration
 *
 */

var config = {
	address: "0.0.0.0", // Address to listen on, can be:
	                      // - "localhost", "127.0.0.1", "::1" to listen on loopback interface
	                      // - another specific IPv4/6 to listen on a specific interface
	                      // - "", "0.0.0.0", "::" to listen on any interface
	                      // Default, when address config is left out, is "localhost"
	port: 8080,
	ipWhitelist: [], // Set [] to allow all IP addresses
	                                                       // or add a specific IPv4 of 192.168.1.5 :
	                                                       // ["127.0.0.1", "::ffff:127.0.0.1", "::1", "::ffff:192.168.1.5"],
	                                                       // or IPv4 range of 192.168.3.0 --> 192.168.3.15 use CIDR format :
	                                                       // ["127.0.0.1", "::ffff:127.0.0.1", "::1", "::ffff:192.168.3.0/28"],

	language: "de",
	timeFormat: 24,
	units: "metric",

	modules: [
		{
			module: "alert",
		},
		{
			module: "updatenotification",
			position: "top_bar"
		},
		{
			module: "clock",
			position: "top_bar"
		},

		{
			module: "compliments",
			position: "lower_third"
		},

{
  module: "MMM-AssistantMk2",
  position: "top_left",
  config: {
    debug:true,
	ui: "Classic", // or "Classic", "Classic2"
    assistantConfig: {
      projectId: "", // Required to use gaction.
      modelId: "", // (OPTIONAL for gaction)
      instanceId: "", // (OPTIONAL for gaction)
      latitude: 51.508530,
      longitude: -0.076132,
    },
    responseConfig: {
      useScreenOutput: true,
      useAudioOutput: true,
      useChime: true,
      timer: 5000,
      myMagicWord: false
    },
    micConfig: { // put there configuration generated by auto-installer
      recorder: "arecord",
      device: "plughw:1",
    },
    customActionConfig: {
      autoMakeAction: false,
      autoUpdateAction: false, // in RPI, gaction CLI might have some trouble.(current version should be 2.2.4, but for linux-arm, Google haven't updated) so leave this as false in RPI. I don't know it is solved or not.
      actionLocale: "en-US", // At this moment, multi-languages are not supported, sorry. Someday I'll work.
    },
    recipes: [ "with-MMM-Hotword.js", "with-MMM-TelegramBot.js" ],
    profiles: {
      "default": {
        profileFile: "default.json",
        lang: "de-DE"
      }
    },
  },
},


{
  module: "MMM-Hotword",
  config: {
	recipes: ["with-AMk2v3_smart-mirror.js"],
    chimeOnFinish: null,
    mic: {
      recordProgram: "arecord",
      device: "plughw:1"
    },
    models: [
      {
        hotwords    : "computer",
        file        : "computer.umdl",
        sensitivity : "0.5",
      },
    ],
    commands: {
      "computer": {
        notificationExec: {
          notification: "ASSISTANT_ACTIVATE",
          payload: (detected, afterRecord) => {
            return {profile:"default"};
          }
        },
        restart:true,
        afterRecordLimit:0
      }
    }
  }
},

	]

};

/*************** DO NOT EDIT THE LINE BELOW ***************/
if (typeof module !== "undefined") {module.exports = config;}

result:
magic mirror does start.
I can speak “computer” and some words like “wetter in zürich” there is a beep and the mmm-assistantMK2 V3 logo starts to be animated and it looks like it expects some input but nothing happens

expected result:
after speaking "computer " and some words the google assistant starts responding

log:

[11:13:22.334] [LOG]    Server started ...
[11:13:22.335] [LOG]    Connecting socket for: updatenotification
[11:13:22.336] [LOG]    Connecting socket for: MMM-AssistantMk2
[11:13:22.337] [LOG]    Connecting socket for: MMM-Hotword
[11:13:22.338] [LOG]    [HOTWORD] MMM-Hotword starts
[11:13:22.339] [LOG]    Sockets connected & modules started ...
[11:13:22.620] [LOG]    Launching application.
[11:13:25.748] [LOG]    [HOTWORD] Recipe is loaded: with-AMk2v3_smart-mirror.js
[11:13:25.836] [LOG]    [AMK2] MMM-AssistantMk2 Version: 3.0.0
[11:13:25.841] [LOG]    [AMK2] RECIPE_LOADED: with-MMM-Hotword.js
[11:13:25.845] [LOG]    [AMK2] RECIPE_LOADED: with-MMM-TelegramBot.js
[11:13:25.846] [LOG]    [AMK2] NO_ACTION_TO_MANAGE
[11:13:25.871] [LOG]    [AMK2] AssistantMk2 v3 is initialized.
[11:13:25.907] [LOG]    [HOTWORD] begins.
[11:13:25.908] [LOG]    [HOTWORD] Detector starts listening.
[11:13:25.941] [LOG]    [AMK2] tmp directory is now cleaned.
[11:13:27.739] [LOG]    [HOTWORD] Detected: computer
[11:13:27.741] [LOG]    [HOTWORD] stops.
[11:13:27.747] [LOG]    [HOTWORD] Final Result: { detected: true, hotword: 'computer', file: null }
[11:13:27.831] [LOG]    [AMK2] QUERY: { type: 'TEXT',
  profile: { profileFile: 'default.json', lang: 'de-DE' },
  key: null,
  lang: null,
  useScreenOutput: true,
  useAudioOutput: true,
  session: 1579428807774,
  status: 'standby',
  secretMode: false,
  sayMode: false }
[11:13:28.816] [LOG]    [AMK2:AS] CONVERSATION:RESPONSE
[11:13:28.891] [LOG]    [HOTWORD] begins.
[11:13:28.892] [LOG]    [HOTWORD] Detector starts listening.
[11:13:58.729] [LOG]    [AMK2:AS] CONVERSATION:RESPONSE
[11:13:58.737] [LOG]    [AMK2:AS] CONVERSATION_ERROR : { Error: 14 UNAVAILABLE: Service unavailable.
    at Object.exports.createStatusError (/home/pi/MagicMirror/modules/MMM-AssistantMk2/node_modules/grpc/src/common.js:91:15)
    at ClientDuplexStream._emitStatusIfDone (/home/pi/MagicMirror/modules/MMM-AssistantMk2/node_modules/grpc/src/client.js:233:26)
    at ClientDuplexStream._receiveStatus (/home/pi/MagicMirror/modules/MMM-AssistantMk2/node_modules/grpc/src/client.js:211:8)
    at Object.onReceiveStatus (/home/pi/MagicMirror/modules/MMM-AssistantMk2/node_modules/grpc/src/client_interceptors.js:1306:15)
    at InterceptingListener._callNext (/home/pi/MagicMirror/modules/MMM-AssistantMk2/node_modules/grpc/src/client_interceptors.js:568:42)
    at InterceptingListener.onReceiveStatus (/home/pi/MagicMirror/modules/MMM-AssistantMk2/node_modules/grpc/src/client_interceptors.js:618:8)
    at /home/pi/MagicMirror/modules/MMM-AssistantMk2/node_modules/grpc/src/client_interceptors.js:1123:18
  code: 14,
  metadata:
   Metadata { _internal_repr: { 'content-disposition': [Array] }, flags: 0 },
  details: 'Service unavailable.' }
[11:13:58.741] [LOG]    [AMK2:AS] >> This error might happen when improper configuration or invalid Mic setup.
[11:13:58.743] [LOG]    [AMK2] { session: 1579428807774,
  error: 'NO_RESPONSE',
  action: null,
  text: null,
  screen: null,
  audio: null,
  transcription: null,
  continue: false,
  lastQuery:
   { type: 'TEXT',
     profile: { profileFile: 'default.json', lang: 'de-DE' },
     key: null,
     lang: null,
     useScreenOutput: true,
     useAudioOutput: true,
     session: 1579428807774,
     status: 'standby',
     secretMode: false,
     sayMode: false } }
[11:18:03.671] [LOG]    [HOTWORD] Detected: computer
[11:18:03.673] [LOG]    [HOTWORD] stops.
[11:18:03.675] [LOG]    [HOTWORD] Final Result: { detected: true, hotword: 'computer', file: null }
[11:18:04.010] [LOG]    [AMK2] QUERY: { type: 'TEXT',
  profile: { profileFile: 'default.json', lang: 'de-DE' },
  key: null,
  lang: null,
  useScreenOutput: true,
  useAudioOutput: true,
  session: 1579429083751,
  status: 'standby',
  secretMode: false,
  sayMode: false }
[11:18:04.592] [LOG]    [AMK2:AS] CONVERSATION:RESPONSE
[11:18:04.921] [LOG]    [HOTWORD] begins.
[11:18:04.922] [LOG]    [HOTWORD] Detector starts listening.
[11:18:34.579] [LOG]    [AMK2:AS] CONVERSATION_ERROR : { Error: 14 UNAVAILABLE: Service unavailable.
    at Object.exports.createStatusError (/home/pi/MagicMirror/modules/MMM-AssistantMk2/node_modules/grpc/src/common.js:91:15)
    at ClientDuplexStream._emitStatusIfDone (/home/pi/MagicMirror/modules/MMM-AssistantMk2/node_modules/grpc/src/client.js:233:26)
    at ClientDuplexStream._receiveStatus (/home/pi/MagicMirror/modules/MMM-AssistantMk2/node_modules/grpc/src/client.js:211:8)
    at Object.onReceiveStatus (/home/pi/MagicMirror/modules/MMM-AssistantMk2/node_modules/grpc/src/client_interceptors.js:1306:15)
    at InterceptingListener._callNext (/home/pi/MagicMirror/modules/MMM-AssistantMk2/node_modules/grpc/src/client_interceptors.js:568:42)
    at InterceptingListener.onReceiveStatus (/home/pi/MagicMirror/modules/MMM-AssistantMk2/node_modules/grpc/src/client_interceptors.js:618:8)
    at /home/pi/MagicMirror/modules/MMM-AssistantMk2/node_modules/grpc/src/client_interceptors.js:1123:18
  code: 14,
  metadata:
   Metadata { _internal_repr: { 'content-disposition': [Array] }, flags: 0 },
  details: 'Service unavailable.' }
[11:18:34.584] [LOG]    [AMK2:AS] >> This error might happen when improper configuration or invalid Mic setup.
[11:18:34.584] [LOG]    [AMK2] { session: 1579429083751,
  error: 'NO_RESPONSE',
  action: null,
  text: null,
  screen: null,
  audio: null,
  transcription: null,
  continue: false,
  lastQuery:
   { type: 'TEXT',
     profile: { profileFile: 'default.json', lang: 'de-DE' },
     key: null,
     lang: null,
     useScreenOutput: true,
     useAudioOutput: true,
     session: 1579429083751,
     status: 'standby',
     secretMode: false,
     sayMode: false } }

Any help would be appreciated… AFAIK it must be a hotword config I messed up. after spending now 4 hours tweaking I reach out to the community ( pls make me and my kids happy :-) )