I know, this topic is a bit older, but maybe any Help is still needed...
This problem seems to occur more often with the turntable. Over the past years, I've had seen so many offers at the famous auction side or the local classifieds with a similar problem description.
And even my HT-350 had the same problem some time ago. The platter needed a little nudge to run. After some measuring of the electrical components on the circuit boards, I came to the conclusion, that two capacitors were faulty. The "bad boys" were the C01 (22µF/10V) and the C02 (0,01µF/400V). After replacing those, the turntable worked normally again.
Hitachi PS-58 with audio-technica AT150MLX;
Cambridge Audio Azur 651A / 651C / 651T / 651P; KEF LS 50
Hitachi HT-6M, Hitachi HA-330 / FT-340 / D-230; Akai GXC-760D; argon audio 6210S;