[MPlayer-users] help with channel manipulation

[Jaume Ferrete]

Hello,

I would like to use mplayer to play mono audio files through selected audio
output channels.

I.e. on a stereo output device, play a .wav file ONLY through left channel,
while right channel remains silent; or the other way around.

Ultimately I would like to do this with a 4 channel device (i.e. focusrite
usb audio interface), selecting which particular channel to output every
time i play a file.

I've tried to understand channel manipulation from docs, and assumed that I
could do something like:

mplayer file.wav -af channels=1:1:0:1

...understanding it as 1 output channel, 1 movement, left channel to right
channel; and thus getting audio output only from right channel. I am
attempting to do this with a mono audio file.

the result goes like:

--
(...)
[channels] Invalid routing in pair nr. 0. [libaf] Reinitialization did not
work, audio filter 'channels' returned error code -2 Error at audio filter
chain pre-init! Exiting... (Fatal error)
--

Could somebody help me understand, please?

Thank you very much