WELCOME to Satellite Guys and to the Glorystar Forum!!!
If as you indicate, it is saying no signal, then it may not be the STB. As stupid as this sounds, I have found dishes that flex enough that they will drop the signal off the "Digital Cliff". Rebooting the receiver causes the receiver to search for the signal and when it finds it, even slightly off fequency it will lock again. Then after the LNBF drifts a little agin, you fall off the "Cliff" again. When you get a signal locked in, again, SLOWLY AND CAREFULLY check the dish alignment- Tweak - as they say. OOPPS before you tweak, check the string test and be sure the dish is not warpped. A marginal aim by itself, or a slightly drifting LNBF or a slightly drifting STB is usually not enough to cause a loss like that, but the combination can do it.
Overheating of the STB is a possibility, BUT since it comes right back instead of a ten minute off time, that is not likely. But that being said, do look inside the box through the holes for dust bunnies.
POP