Installing linux-backports-modules-2.6.31-14-generic-pae, restarting alsa-utils and killing pulseaudio fixed the 5.1 problem for me. I got the center channel working by unmuting it from alsamixer.
Kernel: 2.6.31-14-generic-pae #48-Ubuntu SMP Sound card: Creative X-Fi -- Highpitched Rattling like Sound with 5.1 Surround Configuration on Karmic Koala https://bugs.launchpad.net/bugs/445849 You received this bug notification because you are a member of Ubuntu Bugs, which is subscribed to Ubuntu. -- ubuntu-bugs mailing list ubuntu-bugs@lists.ubuntu.com https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs
