ORIGINAL: Steve
Dude, your servos are not bad. You have a bad Y harness or not enough power. I've solved several peoples so called problems by using heavy duty extentions and 6 volt battery. All of the digitals will do this exact thing when there is not enough power to them and you run a Y harness or dual servos.
That's exactly what I was going to say. Don't use whimpy little extensions with these servos. Also 6 volt batteries are all I use. I never have problems with the 5645's or 5945's.
Try a Heavy Duty Y.