Swap left and right channels

[ranperry]

Is there a way in MPD to swap the left and right channels?

[MaxKellermann]

Yes, with the "route" filter plugin. https://mpd.readthedocs.io/en/stable/plugins.html#route

[ranperry]

Thanks. Is there a specific format I should use? Perhaps an example how this is being used as a filter taking into consideration my card is "hw:0,0".

[ranperry]

Using Raspberry Pi, I tried this. Am I in the right direction? Documentation is pretty thin...

filter {
plugin "route"
name "swap stereo channels"
routes "0>1,1>0"
}

Assuming 0 is one channel and 1 is another?

[herman-brix]

If your mpd audio_output is via alsa, you might consider the following.

The precompiled binary supplied by the Linux distribution I'm using doesn't appear to have the route filter built in so I added the following to /etc/asound.conf

pcm.lrswap {
type plug
slave.pcm "hw:1,0"
slave.channels 2
ttable.0.1 1
ttable.1.0 1
}

The device then becomes "[pcm.]lrswap" in mpd.conf:

audio_output {
type "alsa"
name "[card name]"
device "lrswap"
}

Of course in "pcm.[new_device_name]" the new name can be whatever you like.

[ranperry]

This is the current deice setting:

audio_output {
type "alsa"
name "I2SPi"
device "hw:CARD=sndrpihifiberry,DEV=0"
}

As per @MaxKellermann I should use the filter option which is native to MPD (I guess). There is not enough info or an example I can use so at this point, I am going by trial and error....