Vehicle Making Uncontrollable Movements

-Download my SLS Rocket
-Launch, and achieve low earth orbit
-If orbit is not achieved with first stage of SLS, point rocket to east and 0% height, --stage sep to 2nd- make sure throttle is at 100%
-The vehicle at this point may legitimately try to point itself towards where you want it to go
-cut throttle to 0%
-The vehicle, if I'm not crazy, will make irregular movements, draining battery while doing so. If you unlock the heading, it may be worse
-For comparison, stage sep to third, and the vehicle should act normally

=NOTE=
-The strut looking things on the second stage are present to replicate the real rocket, they are all "strut" parts, I used to have a soyuz interstage in the place of those struts, it was only there for decorational purposes, the rocket did the same thing with that soyuz interstage piece on the rocket.
-Also, this anomaly did occur previous to the recent Beta update.