loops automatically and randomly changing key

ok, here's the deal

I am making a song that is entirely made up of software instruments written by me and transfered into the computer via musical typing. The verse plays perfectly, but during the bridge and chorus, something weird happens. The loops will just randomly change key, and it sounds horrible. I believe it is a different key they change to everytime as well. It is not having anything to do with pitchbend or modulation or any of those advanced editing tools, I already checked. I am totally stumped. What would cause garageband loops to automatically switch to a different key?