Some more information: Headphone output provides proper stereo audio despite the speaker problems, so my guess would be that this is a sound driver bug, not a Pulseaudio glitch. Apt logs indicate that many ALSA- related packages were updated right after I installed 10.10.
-- [VIA VT1828S] Only getting mono sound with 10.10 https://bugs.launchpad.net/bugs/637429 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