There's a capacitor on the coin comparitor, it's in the circuit for the solenoid that works the coin rake, I think that replacing that capacitor sometimes helps with the buzzing. You can also feel to see if any of the mechanical moving parts are overly loose and chattering. For home use people sometimes disconnect the solenoid to quiet it, you would need to force the rake into the "coin accepted" position by sticking a folded piece of paper or similar under it. But that would let all deposited coins go to the hopper, so someone could slip a smaller coin into the machine and cause a hopper problem. You can get a replacement cc for not a big cost.
I think all of those player deck pushbuttons have bulbs inside, but you can check by looking up from the bottom to see the wires going to the buttons. There will be a pair of wires for the button switch and a second pair of wires for a bulb if there is one. The exception might be the dark red colored button over to the left side for change/call attendant, I don't think it has a bulb inside. Basically, if the pushbutton has a clear or white lens there is probably a bulb inside.