OT: Denon Turntable Help

I recently purchased and received a Denon DP-23F fully automatic turntable from a seller on eBay. After cleaning it up and installing an Audio Technica AT440MLA it sounded fantastic (looks almost new as well, especially considering it had a date code of 12/88 - so its 22 years old.) Anyway the tone arm is not automatically returning and the repeat function is not working. If I press the stop button, the tone arm returns flawlessly and the auto start is perfect. Any ideas on what could be causing this problem and how I could fix it?