i have the original stereo the car came with still and recently im starting to have a small prob with it. when i have the car turned off but the stereo still on, the stereo will turn itself off then after a few seconds it comes back on and is fine for the next few minutes before it repeats the process altho i havent noticed the problem while the car is on. i think i noticed that if i put it on a volume of 21 or higher, thats when this happens. i have installed and amp and subs awhile back but this prob is just now. any ideas whats causing this or a possible solutions? thanks