deferce,
Often, high-pitched sounds within a DLP can be attributed to the color wheel. You might want to schedule a service tech to come out and take a look, but that may be the cause of the noise.
Hope that helps.
--HDTech
Good morning. At turn on lamp tries to light 3 times- visible through back of unit. It makes a loud, hi-pitched noise while it starts and then the unit shuts down. The lamp is new. Thanks if you can assist me-Mike

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