Flaky Potentiometers

[theDoctor]

We're using two potentiometers on the RC analog inputs to measure angles on our arm. I've been monitoring their values through printfs. Sometimes I get lovely and normal values (0-1023), and sometimes I get very strange ones. In strange mode, the values always increase, but in this order: 0 64 192 448 960 1984 4032 7680 7936 8128 (...) The first few numbers follow an obvious pattern but I don't know where the 7000 ones come from. And after that it gets less regular. It goes up to numbers like 32768 and above.

This confuses us in programming, because the function that reads the analog inputs should never return a number above 1023, so it looks like interference. We've wiggled our pwm cables and so on but it doesn't make things better. Um...I assume this is an electrical problem. Does anyone know where this is coming from?

Thanks.