Fruit Machine Chat

Hi there, I wonder if anyone can help. I have an original Maygay The Great Escape machine from around 1997. It is in good working order with the exception that there is no sound. There is a high pitch buzzing sound coming from the speaker and the volume control is turned up. When entering the sound test function again there is no sound. Anyone have any ideas?

Open the front door (if yellow surround/hopper), otherwise it's hoik off the back if black cab + tubes. Go into test, turn the volume to a reasonable level so as not to give yourself a heart attack.
Now locate the speaker whilst test is still on volume and you'll see a cable containing two wires that attach to a little metal portion of the speaker. Jiggle this about a bit and see if you hear any sort of coherent sound.
If you do, chances are connection there just needs a clean up and a solder.

If you don't, chances that sound EPROM is kaputt, or some other explanation which someone may be able to explain.