Comment 4 for bug 669729

Pulse relies on the drivers providing accurate information, and that doesn't
seem to be the case here. You can manually hint to pulse that it should
fall back to the interrupt-based mode by passing tsched=0 to
module-udev-detect in /etc/pulse/default.pa, but I can't tell if that's
necessary here. Please see https://wiki.ubuntu.com/PulseAudio/Log. There
are also msec* tunables, but we should first establish that you need them.