Boneyard shenannigans -SOLVED!!!!

[wgc]

Always possible that yours is/was something else, but I'm almost certain this was a contributing factor on mine.  Especially when I think about the internals of the switch.
If my next build has a similar squeal, I know what I'll try first.

[Willybomb]

Tried out a couple of different charge pumps, no luck, so sticking to the resistor.

[Willybomb]

Ok, this has just gotten wierd.  I plugged Ammocan into Boneyard, into Terminus, into my PA speaker.

I have the whine back on the low gain channel when it's dimed - but there's no whine on the hi-gain, or when the boost is engaged on the hi gain channel..  Better go back and see what happens with low-gain+boost.

Work that crap out.