I have an 1800 that won't automatically lower the tonearm when you press start. It moves over the record and just sits there. If I press Cue, it works fine. I've also noticed that if I take the platter off and weigh down the size selector with a heavy spool then it works normally. Once I put the platter back on, it goes back to not lowering the arm. These results have been surprisingly repeatable and frustrating. The platter doesn't appear to be rubbing on anything and I've already cleaned the micro switches under the platter. Do you guys have any ideas? How does it know to trigger the second gear to lower the arm during an automatic start?