RE: oscillating servo
Roby
It sounds like you have a dirty potentiometer in the servo, if you have the nerve and experience you can take it to pieces and clean the pot with a propriatary switch cleaner, these normally come in an airasol with a tube extention, you can force the cleaner in at the top of the pot once you have removed the gears and therefore do not have to dismatle further, try just squirting some cleaner through the servo arm spline, it may work sufficently if your pot is not too dirty.
Mike