module-remap-sink distorts when remapping to mono from stereo

[sladi]

When I do

pactl load-module module-remap-sink sink_name=test master=front_stereo channels=1 master_channel_map=aux0 channel_map=mono

I get distortion. I can lower the volume of a virtual sink and remap that in order to remove the distortion. I believe a LADSPA amplifier sink lowered by 6dB is enough.

I use PA 0.9.16~test2~20090726git59659e1db-1 and RC888 soundchip.

[sladi]

I excpected remap to mix to mono but it adds up the volume. There is workaround as I wrote above.

Regards, Sladi

[coling]

A likely related thread on the ML: http://thread.gmane.org/gmane.comp.audio.pulseaudio.general/4353

[sladi]

IIRC there was a comment by Lennart why you just don't remap twice to left?

I tried that but then you only get one channel (left) playing. With mono both channels are added and this is what you usually want from mono output, i.e. all channels played back on one speaker.

[sladi]

Replying to sladi:

IIRC there was a comment by Lennart why you just don't remap twice to left? I tried that but then you only get one channel (left) playing. With mono both channels are added and this is what you usually want from mono output, i.e. all channels played back on one speaker.

Yes it was in the above link: master=alsa_output.pci-0000_00_1b.0.analog-stereo master_channel_map=left,left plays back only the left channel.

[lennart]

What are you actually trying to do? Using aux0 in the master channel map doesn't make much sense to me.

Have you checked out the multiplication matrix you can see in the -vvvv output of PA when module-remap-sink initializes?

If all you want to do is just create a sink whose signal is send out on the left channel only then i'd try:

channels=1 channel_map=mono master_channel_map=left remix=0

[lennart]

I think this issue is mostly a misundertanding on how remixing works, and the fix is the remix=0 switch.

If there is really a problem here and I just don't understand it then please reopen and explain again!