I've had a H6502BD projector installed for a year or two. Recently, it's started shutting down about once a night after a few hours of operation. It emits three fast beeps, turns off the lamp but keeps the fans running for about 5 seconds. During this time both the power and lamp leds are lit. The case is warm to the touch but not overly hot.
If we wait a few minutes and turn it back on it seems to run fine again, but we have had several shutdowns in one night before.
I've opened the top and inspected the lamp, removed and reinstalled it, and checked all the fans and vents and such and they all look okay. I've also blown compressed air through (when it's cold, of course) to make sure there's no dust stuck in there. According to the on screen display the bulb time is 3200 hours.