On Mon, 2014-02-10 at 22:28 +0100, David Henningsson wrote: > Are you ok if I push this one to master (just this one, not the chmap > API one)? What's the definition of the surround21 device in alsa? Is it "four channels with channel map front-left, front-right, lfe, discarded"? If it's that, would it be better to use aux0 as the last channel instead of duplicating lfe? I'm thinking that the duplicated lfe may interfere with remixing. For example, when recording a stereo stream from the 2.1 sink monitor, does the lfe channel get downmixed twice? If the last channel is discarded, it would be better to set the sink channel map to just "front-left, front-right, lfe" and generate silence for the fourth channel inside the alsa sink. I don't think that's possible with the current infrastructure, however, and I'm not suggesting that you should implement that, so this is just an idea for future work. -- Tanu
