[Qbranch]

Well since those servos use a linear carbon filament pot for feedback, and simply use proportional control for positioning (Just P, not PI, PD, etc...) then if your supply voltage to the servo(s) is/are too low (I believe 5v is the absolute minimum) then the voltage reference onboard the servo for the analog feedback may be skewed... or it might dip too low whenever the servo attempts to move... causing a 'twitch' as the position the porportional chip in the servo gets back would vary with a low voltage reference. Maybe when you write to your EEPROM your voltage dips ever so slightly and this occurs.

Or, as a more probable option, some EEPROM uses a very high voltage to flash the bits into memory. This could theoretically casue a high voltage spike to go out of the processor as the lines driving the EEPROM decay after flashing a bit in.

Maybe i'm barking up the wrong tree... but it sounds like most other things have been defined as working.

-q