I have an interesting problem. I have my PC hooked up to my surround sound (7.1) system via an optical cable.
If I play a DVD in mplayer with hardware AC3 passthrough turned on, I get full surround sound through the speakers. This bit is fine.
Any other sounds played through the system come through the front speakers only. I've verified this by trying
speaker-test -c 8 -t wav
Sound only comes out for the Front Left and Front Right channels, even though the rest of the channels are printed. I've also tried testing it with 6 channels instead of 8 to no avail.
I think the problem might be that the optical GIGABYTEoutput is only encoding the front channels' signals, and not the surround channels, but there's no way to change this in the volume control. There is a channel mode, which has two options, "6ch" or "8ch". Changing it seems to have no effect.
Any ideas, anyone?
This is an onboard soundcard on a Gigabyte GA-P35-DS3L motherboard. The sound card is an Intel ICH9 with a Realtek ALC888 chip. It uses the snd-hda-intel kernel module.
Thanks in advance.