1. The spindle speed on the display is always what is commanded, if I have called 1500 it reads 1500, whether the spindle is really running 750, 1500, or 3000.
2. Frequency and analog voltage jive exactly with whatever rpm the machine is running, regardless of what is/was commanded, if I'm running 1500 I have 3V, 3000 I have 6V, the VFD is behaving correctly.

I'm hoping this is a result of bad chips at U18 and/or U17 and I can replace chips rather than change out all sorts of stuff.