10X that, actually. It's MIDI.

I saw that errata & tried bumping the register values (from 39 to 38 and 41, also from 9 to 10 and 8) but without much joy.

The other wrinkle is that even if I tune to 3,200 uS, I'm (maybe) in trouble if a properly timed datastream ever appears.

Hmmmm.