Although I am not acquaint with that particular TV, as an engineer (non JVC) I can say that what you describe is a clear cut case of what would suggest an intermittent heat related problem cropping up in the internal circuitry which is causing the power supply to shut down into its standby state for protection purposes. (i.e: the power light blinking) If you keep using the set whilst being aware that a problem exists, the shut down circuit "may" fail at some point resulting in component damage, and so you dont really have any option but to have this checked out by a technician experienced in working with large projection TV sets. (Possibly a strongly worded letter to JVC customer services detailing the circumstances "may" bring results like a subsidised repair?)

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