I just had the same problem with my Panasonic Home Theater. Talked to support, and they said that it probably needed a new power amp, ic501 (I think). Searched the web and was told to check the cooling fan on the back of the unit. It wasn't spinning. There was another small fan inside that would spin for 10 seconds or so, and would stop. After pressing the power button, I spun the fan with my finger (as best as i could) and the unit powered on, until I stopped spinning. I took it out, cleaned it, and the unit worked fine. A new power amp unit is $95, this cost me nothing, but even if I needed a new fan, it has to be less than $5. Good luck.