There may be a problem with your wiring, but you should not use Arcade Drive for things besides your Drive Train. Please see this post for information on how to correct this:
http://www.chiefdelphi.com/forums/sh...3&postcount=14
This is the 2nd time today I've seen teams use a RobotDrive function for something not dealing with a drive-train, and I've never seen this before. Any ideas why?