Ballast making High pitch noise

[Spelter]

One of my ballast has started making a high pitch noise and is hotter than usual. I assume this means it is going bad. Is there anyway I can fix this or is it just a replacement sort of thing? 

[davelin315]

Need to pop it open and see what part is at issue. Could be simpler to replace, but check to see if there is a fan or if you have a shorted part.

[Spelter]

great Thanks I will pop it open and take a look. I figured might be sometihng simple. 

[Coral Hind]

Normally two things cause this humming. One, is how the ballast is mounted as it can vibrate and make a buzzing sound. The other thing is the laminated steel plates of the core over time start to come loose and this will generate buzzing from the plates vibrating against each other. As the vibration gets worse from plates de-laminating the core will suffer hysteresis loses and the ballast will become inefficient. Now is probably a good time to start looking for a replacement as it will only slowly get worse if it is a core plate issue.