Rockola Tempo1

Can anybody help please?
My Tempo has developed an annoying and rather alarming fault.
I have owned the jukebox for about thirty years and only ever needed the Amp servicing, however twice now the same problem has occurred.
When the machine has been off for a long time and everything is cold the jukebox will select and play but when it gets to the end of the record the arm wont lift and return the record. At the same time a horrible burning smell occurs and smoke appears inside the machine. I have turned the machine off to try and find where its coming from, its not the amp but somewhere under the mech cover. It plays fine most of the time but twice this has happened, i think it must be something sticking and overheating, any ideas?

Hello L,
are you still reading these literal highlights from the 60s?
Regards PitinWHV.