I've got the same problem. Mysterious sounds when changing volume. I'm using 5.1 analog output on Intel Corporation 82801G (ICH7 Family). Rear channel doesn't work too.
I've tried to install some old PCI Creative sound card (SB0460 I guess), and as someone has already described, noise dissapears, if I set 7.1 output, but central speaker stops working - though rear works fine.
Unfortunatly, there are no 7.1 output for my current sound card, so for now I enjoing hissing.
I've got the same problem. Mysterious sounds when changing volume. I'm using 5.1 analog output on Intel Corporation 82801G (ICH7 Family). Rear channel doesn't work too.
I've tried to install some old PCI Creative sound card (SB0460 I guess), and as someone has already described, noise dissapears, if I set 7.1 output, but central speaker stops working - though rear works fine.
Unfortunatly, there are no 7.1 output for my current sound card, so for now I enjoing hissing.