sony cdx-gt57up 52w x4 new /4 polk 100w speakers new,,,,stereo sounds great at low volume,turn it up loud enough to hear at road speeds stereo gos off and comes back on in a few seconds...repeting till l turn the volume way down....lve double checked all wireing voltage on red and yellow..and ran a new ground wire from the battery......some one have a clue,,,,,sanddog