Turntable's Auto Arm function is messing up?

I have a Denon DP 300F automatic turntable and starting yesterday, when I pressed 'Start' the arm would go to the middle of the record and start there. It was always the same point, even for different albums. I thought it might be the tracking force, so I bought a Shure SFG-2 and set the tracking force. Today I played a record (a different one) and the arm did the same thing, it moved to the same spot in the middle of the record (around the end of Track 3). I can still manually start albums, but the auto start/return function is pretty convenient, so I was wondering if there was a way to fix this? Thanks!