Hi. I have a 1994 Mustang GT. It came with the Mach 460 stereo system. I have replaced the head unit and used wiring harnesses provided by Crutchfield to wire in the power and amplifier connections. Every once in a while I will get what seems to be alternator noise in the system. I know its not the new head unit as it used to do this with the old factory head unit, which I had to replace because the volume buttons stopped working. It does not hum all the time. Sometimes it will not hum at all, most times it will start as I am driving. I have noticed that alot of times it will start humming when I am on the brake, either stopped or coming to a stop. Turning the radio on and off usually corrects the problem, at least temporarily. Also I'm not sure whether car temperature plays a role. I know it will hum when the car is warm, not sure if it would happen when the car has just been started. I have checked the connectors and they seem to be ok. I've tried checking the grounds but the only ones I could find were the two near the battery and one on the other side of the front engine bay. I know there is one near the inside instrument panel fuse box but I haven't been able to locate it yet, so I dont know if thats my problem. If anybody knows anything that would help, or a way to correct it please let me know. If you have questions or need more info let me know and I'll reply as soon as possible. Thanks!
Justin
Justin