I had a capacitor on the power supply board(52315-A) inside the amplifier(52280-A) pop on me whilst the speakers were off and disconnected from the wire that connects the amp to the speakers.

I have since replaced the capacitor that popped on me which the manual lists as C67, but ever since I have plugged it in with the new capacitor it just does a constant humming even if I'm not playing a record in it.

Video of the hum: https://www.youtube.com/watch?v=CX4Y_bRui1A
I can provide more info if needed