Leaderboard

I would expect the third digit after the decimal to change from bit and electrical noise. The bit resolution with the input set up for +/- 5V will be 0.15 mV, so the bit noise is in the 4th place after the decimal (assuming you're not gaining in software by 10 or more). Chances are you're seeing electrical noise. Multimeters have some time averaging in them that will eliminate what you're seeing through the 9205. It's certainly worth checking over your wiring, perhaps verifying with a battery, and looking for ground loops (evil things!). You've not mentioned behavior that would lead me to think you have a wiring problem. (A lack of understanding, yes, but wiring problem no.)

I like it. I've always liked the ability to dynamically query an object at run-time for a given interface as is done in COM. For those who aren't familiar with COM and the trick that's getting played here, I've annotated the key thing that's happening with wire colors. You can do some pretty cool things with the PRC primitive indeed. Well done, candidus.