Playing multiple sources at the same time with mopidy

General
1

Hi All,

i wonder whether is it possible to mix two mp3 sources in real time with mopidy, so the user can listen them as one stream.
for example a live stream is playing, and in case of an incoming message i would like to inform the listener about the event.
any feedback is highly appreciated.

2

An ALSA dmix plugin allows multiple processes to use the same audio hardware at the same time. E.g. Mopidy and your event sound playing program.

3

huge thanks for the answer. i’m going to check the dmix plugin!

4

I had the same challenge and just worked around Mopidy. As kingosticks mentioned, you can just use a “dmix” sound output for Mopidy and another application in parallel.

$aplay -L
...
dmix:CARD=system,DEV=0
    ADD ON USB Cinema system, USB Audio
    Direct sample mixing device
...

Then use mpg123 or another sound player
/usr/bin/mpg123 -a dmix:system welcome.mp3 >/dev/null 2>&1

5

I made a post about doing something similar to what you are talking about using pulseaudio here https://community.home-assistant.io/t/text-to-speech-and-music-at-the-same-time/172899. Although the post is geared toward Home Assistant the concept should work for anything that can connect to pulseaudio.

6

thanks for all the answers!

7

I’ve been trying to get dmix working with Mopidy.

What did you add under
[Audio]
in the mopidy config? I have tried many things like:
output = alsasink device=pcm.dmix
output = alsasink device=dmix
output = pcm.dmix
output = dmix
output = alsasink device=plug:dmix
output = plug:dmix

But none worked.
I have searched in this forum but all I find is different use cases or over and over the sentence “You should be able to configure an ALSA dmix plugin” but never really a proper how to.

I have dMix working with shairport by adding the line:
output_device = “pcm.dmix”
But as mentioned above the same does not work with mopidy.

Any help is appreciated, I have spent hours and hours trying to make this work. I’d say that is my last try to get mopidy play along, then I will probably have to move on to another player or even volumio…