Hi Fengguang, > Hmm it seems there are zero memory allocation delays, so it's at least > not the root cause of the qemu delays in my case. Can you run a sanity check with the tsched=0 option at the end of the module-udev-detect line in your /usr/etc/default.pa file? This will disable the use of timers and instead use the ALSA period events to wake-up the real-time thread. PulseAudio will then behave as a traditional ALSA front-end. If this works, then it means the logic behind the timer-based scheduling fails in your system. -Pierre
