HURCO KMB-1 Control Update

Delving into this in more detail, the AtoD conversion doesn't look very stable.
My digital voltmeter reads on a nominal mid position of XY feed pot a steady, non varying 1.666v
the 7i73 analog0 numbers flicker, not regularly, like on a timer, but with a fast random up and down.. With a slow-mo video
I actually get readings 1.565882,1.578824, 1.591756 the differences are exactly one bit. (3.3volts, 255 bits, ie 0.012941 volts per bit)
When the servos are on, then this flicker is actually audible.
Can you suggest anything that I can do to improve this please?
Thanks

You can low pass filter the outputs
Also for noise and stability I would

1. Run the pots from the 7I73s 3.3V if you can
(Since this is the 7I73s analog input reference the reading
will be ratiometric, so a change in the 3.3V will not change the reading)

2. Low pass filter the inputs at the 7I73 (say with a 0.1 uF capacitor to 7I73 ground)

3. Low pass filter the analog hal signal (a 1 LSB  dither is expected with almost any
A-D at least at some (halfway between) input levels)

Thanks Pete,
Have looked at the trace with a scope now. The 0.1uF smooths out the sawtooth, but I still have this variable voltage flicker that's not caught on the meter, so something adrift with that power supply I think.