I'm concluding that pd runs csound (via [csound6~] ) directly in some way -- and that the instance of csound it's running does have access to the system outside the csound6~ interface:

for example, if I put a widget in the .csd file I'm playing, it normally won't get displayed. But If I put it in a widget panel in the file, it does -- not through pd, correct?

If I just wanted to use pd to send controls ( via [HID] for example), I'd expect I wouldn't need to run pd at dsp rate, could have the csound instance send audio directly to dac...

but putting the -odac flags in the .csd file doesn't seem to do it. [These do work if I run the same file via command line.]

Is the audio from [csound6~] trapped within the interface somehow? Or is pd grabbing the dac even when I use 'Audio Settings' to turn 'Input device 1:' off?

Is there an easy fix? -- or would I do better to just run the audio back into pd & out via [dac~] as is customary?