CSS-64 Buzzing sound

[Pixel]

I sometimes hear a buzzing sound coming from my mother's CSS-64 when I grab a soda from it. The buzzing has a very electrical sound to it. The places I know to look are the coin mech, the vend solenoid, and the marquee lamp ballast. The coin mech has stopped activating the vend solenoid. We put cans in the machine, but I sometimes check the coin mech anyway to make sure the vending system is working. The sign is not lit up, I think the bulb's went bad. I wonder if the ballast is going too.

Has anyone else had this problem? Which one is more likely to be the problem?

[Yarochrehc]

Have you unplugged the coin mech. to see if it stops?

[Pixel]

I will, but if the vend solenoid is causing the buzzing will it still buzz with the mech unplugged?