Stereo & Electronics - Head unit turning off on its own

First off, I did a search and checked the faq's, but couldn't come up with anything. I had the stock head unit, and it would cut out on me every now and then. It seemed to be bad in the summer when it was really hot out. I dont know if it did it when I bought the car, because I took it home and put an amp and a sub in same day. Since then, I have taken out them both, and now recently got a new pioneer head unit. Still doesnt stay on. I can hear it when it cuts out, the amp is turning on and off. It doesnt reset the time or my stations, so the aux power is staying on. I have check all my connection several times. Not sure what direction to go in next. Any ideas?

mine does the same thing they told me it was in the wiring but i have no idea how to find out where in the wiring, im taking mine to the local car audio place and having them figure it out for me, i figure its chaeper than me messing with wires and really messing something up