It's a bit late only just looked in adding that in case you are still looking for solutions.
MY thoughts are BELT drive I had a music centre with same thing the disc would not turn took it apart and it was the drive pulley belt (thin rubber ring) had broken so the drive was going but not the Disc replaced with eleastic band. (Some belts stretch too so drive slips)
Remember never stop a spinning disc let it stop on its own as stopping by hand can also damage drive.
bob uk, June 2017