Car Stereos: audio interference, power line noise, power line filter

Question
hi, i did test the headunit and the hum came out of the standard speakers when the volume was on full. Also i heard that the supressor is meant to cover up the hum. Would a new headunit be the answer? I wired it up correct as i tested the wires with the meter and used a toyota diagram. Also if i turn the volume up quick somtimes i get a poping sound from the speakers. Also using the rca convertor. Thanx

Answer
Hi Danny,

It does sound as though the problem is in your head unit.  I suspect a replacement head unit will be the easiest fix.  

Power line noise filters aren't used much any more because most car audio equipment, OEM or after-market, has noise filtering built in.  It's possible that the noise filter in your head unit is defective.  In that case, a power line noise filter might help.  However, if there's some other internal problem causing the noise, a power line filter won't help you, and you'll probably need a new deck.

As I said before, it won't hurt anything to try the noise filter.  If it works, great; if not, you can start shopping for a replacement head unit.

Good luck!

Brian