After the results of the analysis in the #8598 thread, I have added the "no_zero_pad=1" flag to the cdsParameters block of all SUS models:
The upsampling to the 64 kHz DAC output will now be done with sample-holds, instead of zero-pads. This should reduce the 32 kHz lines we were noticing in the analog DAC output.
I note, though, that Brian Lantz points out that this might actually introduce a delay of about a half sample. We will continue to investigate.
In any event, I have rebuilt and installed all models listed above. I will restart as soon as opportunity allows.