I am running an embedded system using pulseaudio and alsa.
I need to downmix all audio inputs to a single mono output.
I have seen other answers that involve modifying /etc/pulse/default.pa
like the example below.
https://askubuntu.com/questions/17791/can-i-downmix-stereo-audio-to-mono
I have tried this, but it doesn’t seem to work while in system mode.
When I try to run the pulseaudio service as the pulse
user it seems to be reading the file /etc/pulse/default.pa
but I get an error: failed to open module "module-remap-sink".
I am OK using either ALSA or pulseaudio to achieve mono output. How can I achieve this?