I have the Johnny 5 and i notice on power up the bottom two servos it seems near the base will buzz a little bit, and I felt these servos and they are pretty warm to the touch. I’m not sure what is considered hot but they seem pretty close to that, what casues this and is it a fixable thing? when powered also the arms kind of jitter to whats the cause of this? I thought maybe because the servos arent centered good.
Servos doing work will heat up. You must observe this when experimenting and take care not to let it get out of control. The only way to eliminate this in the torso servos would be to use the HS-755 and the large scale brackets. They didn’t even exist when the J-5 was designed. The larger servos do not heat up nearly as fast as the standard size servos do.
More along this topic, don’t move the arms so the shoulder servo is holding up the entire arm, and leave it that way while you go to lunch. 
I try to convey to the newer builders to think of it in real people context. You wouldn’t be able to hold your arm outstretched in front of you for a long time. Robots can’t do it either.