> For normal alsa playback, their typical values are 1024. ?Pulseaudio > sets them to large values and maybe is not entirely depending on the > poll. It may be setting some timer to wake up itself when the DMA > buffer runs low on data. > > Anyway the pulseaudio's large buffer scheme makes possible the 61ms > pa_simple_write(). Qemu is not expecting such a large latency. Its > QEMU_PA_SAMPLES defaults to 1024, which can only hold up to > 1024/48=21ms samples. So the 61ms delay will obviously overflow the > "data push" based USB audio model.. The default PulseAudio configuration is 4 periods of 25 ms each. You can reduce this if you want by changing the relevant fields in /usr/etc/daemon.conf -Pierre
