rockola fun!
Based on your question, i would say that the power supply, is where i would start first. There are 8 fuses here to check. Some are outside, and some are inside. Just be sure to turn off the unit first, and allow at least 1 min for the capasitors to discharge. Check the fuses with a meter, because the old glass fuses can still break beyond the site of the glass, breaking at the ends, and would still appear to visually be ok. Now if all tests ok, then its possible that the unit would need to be replaced. However,, in the manual, there are testing procedures for the power supply, using a meter. Hope this helps
P.S. Am i correct in assuming that before it quit all together, that it was pulling records from the wrong slots???? This could lead to another issue. Let me know