Hi, I changed the alternator had battery checked and all fuses are good.my problem is my car stereo shuts off only when I turn my headlights on or go above 22 volume on my kenwood CD deck it seems like the HU is not getting enough juice everything else works fine. please help me find out what the problem is! its frustrating cause I cant listen to music while driving at night from work, thanks

Sounds like you may have a few possibilities. Did you cut off the factory radio connector when you wired it in? I would make SURE your radio is correctly grounded for one. Is there a chance you used the dash light wire as power for the head unit? The more you dimmed your dash lights the quicker the power requirements of your radio would exceed the reduced voltage, possibly turning off the radio as you describbed.