[pulseaudio-discuss] Question about setup sink/source

[andreas.unterhuber at me.com]

Dear pulseaudio community,

I've a setup to run a screen grabber (ffmpeg records content of a website, loaded in chromium by selenium) within a docker container. Audio is recorded from ffmpeg by pulseaudio on a Ubuntu 18 system. 

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My setup: 
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... start Xvfb, chrome+selenium ... 
pulseaudio -D --exit-idle-time=-1
pacmd load-module module-virtual-sink sink_name=v1
pacmd set-default-sink v1
pacmd set-default-source v1.monitor
... and then ffmpeg -ar 44100 -f pulse -i default [...] out.mp4 ... 

Works perfectly. But I want a little more. I'm pretty sure that someone can help me!

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Needed change 1#
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I need an audio source that has always audio (audio "silence"). The browser does not always have audio-websites to playback. So I had in mind to create a source with continuous silence, mixed with browser audio (whenever the browser has audio signals to play). 
How does the command/setup looks like? I played around but was unable to realize... 

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Needed change 2#
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Instead of just continuous silence I want to playback an audio file that runs in a loop forever, mixed with the browser audio. 
How does the command/setup looks like?


I'm very, very thankful for any help!
Best, Andreas