Other observations (tested with Dreambox dm7020hd).
1/
When I start the Mirror, I no channel is selected.
Then when you do DB-PLAY as first remote command, the list on the Mirror will have a grey background (as if everything is selected) and nothing is streamed.
2/
When you do DB-PLAY, I get multiple streams.
I reported this before.
pi@MagicPi:~ $ ps -eaf | grep omxplayer | grep -v grep
pi 20862 20720 0 22:14 ? 00:00:00 /bin/sh -c omxplayer --vol -6000 --win 0,625,590,957 --live http://192.168.178.28:8001/1:0:1:2EE3:441:1:C00000:0:0:0:
pi 20863 20862 0 22:14 ? 00:00:00 /bin/bash /usr/bin/omxplayer --vol -6000 --win 0,625,590,957 --live http://192.168.178.28:8001/1:0:1:2EE3:441:1:C00000:0:0:0:
pi 20886 20863 7 22:14 ? 00:00:17 /usr/bin/omxplayer.bin --vol -6000 --win 0,625,590,957 --live http://192.168.178.28:8001/1:0:1:2EE3:441:1:C00000:0:0:0:
pi 20894 20720 0 22:14 ? 00:00:00 /bin/sh -c omxplayer --vol -6000 --win 0,625,590,957 --live http://192.168.178.28:8001/1:0:1:2EE3:441:1:C00000:0:0:0:
pi 20895 20894 0 22:14 ? 00:00:00 /bin/bash /usr/bin/omxplayer --vol -6000 --win 0,625,590,957 --live http://192.168.178.28:8001/1:0:1:2EE3:441:1:C00000:0:0:0:
pi 20921 20895 7 22:14 ? 00:00:17 /usr/bin/omxplayer.bin --vol -6000 --win 0,625,590,957 --live http://192.168.178.28:8001/1:0:1:2EE3:441:1:C00000:0:0:0:
3/ After a while the selection of a channel disappears.
The selection sometimes is just a grey background and sometimes a grey background with a play button.
4/ My Dreambox has 2 tuners.
I probably see the “now playing” from tuner A, whilst tuner B is streaming.
As the selection disappears, I do not know which channel is streaming.