I built my first few record players from what was available in the local electronic store. When I did my first stereo one, it used a valve amp intended for a different enclosure, and was sort of shoe-horned into the case where the speaker would have gone otherwise. Being a valve type, it was awash with big knobbly high power resistors to drop voltage, which got hot. Due to the realignment, one of these was, as I discovered, now directly below the main smoothing condenser. Over time, this cooked, and blew its vent, emitting a large cloud of evil smelling smoke.
The record being played at the time? An Acker Bilk LP.
The track? Nobody knows the trouble I've seen.