Toshiba 42HM66 DLP makes a high pitch Hum that starts on power up. This buzz has increased in length from a few minutes after power up to all the time now. after removing the back I have narrowed it down to the area around the DLP section. Lamp fan is quiet so I'm thinking ballast fan or the ballast itself. Any info to a solution will be greatly appreciated.
Thank you for the question - I had to look up DLP & now know a little bit about it...
High pitch hum will be high frequency so it won't be a regular mains frequency fan. You might try a wooden spoon as a stethoscope to narrow down the source of the noise - make sure it's perfectly dry before you press it to your ear.
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