I've got some multichannel (5.1) FLAC files and they play fine, e.g. they don't crash Cog or sound glitchy. But I'm wondering: does it mix down for stereo output or does it just take the front left & right channels and ignore the rest?
Edit: Figured it out by d/ling a multichannel WAV file that just identifies each channel. It is the latter: the additional channels are just being discarded. I figured; it sounded kinda weird.