this one works really well with only about 4 ms measured latency at 64 samples hardware buffer.
although this is really good news i'm curious ... which sample rate have you been using? at 44100 and 2 * 64 samples it should only be 2.9 ms ... (2.6 with 48000) ... possibly we lose another 64 samples somewhere in the dsp tick (miller?)
There is a small problem just as before seemingly not related to the scheduler stuff (mainly after changing the hardware buffer size) which sounds like half-filled buffers. A new problem is the loss of adc input at some point. I'll report more detailed later on.
i'll check it later ...