> 3) In the latency reported by module-loopback.c, the second number > (i.e. > the internal jitter buffer) dominates, both in USB => same USB and USB > => onboard audio cases: 63.91+733.32+11.65 ms > > So, for me, it looks like the USB master clock (from which the USB > audio > clock is derived) is too unstable WRT the system timer as a reference, > but this doesn't apply to the "internal audio vs system timer" > situation. Nah. It's more a configuration issue. I tried with pactl load-module module-loopback latency_msec=20 and I get a really low latency. Can you play with this latency_msec parameter and report the log? Thanks, -Pierre