Sounds like a simple solder crack or something. If you know how to solder take the back off and see if you can see any cracks. Be carefull. Unplug it before you take the back off, and do not touch the big red wire going into the side of the tube. Well, just dont pull it out.

If you dont know anything about electronics though it might just be best to take it to someone or just buy a new one.

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