I just replaced my factory speakers with Alpine 6.5 and 4 inch along with an Alpine 100WX4 amp. I turn down the gown quite a bit but still have an audible background hissing that is very very annoying. Anyone know what I can do about this?

Is it possible that there is a factory amp? So you are amplifying and amplified signal?

sounds like engine noise? alternator whine ? check grounding points, should have as few as possible, make sure gauge is same size for both power and ground. make sure amp isnt digging into the body of the car on one of the corners, clean your distributor cap out. and maybe respond back.

btw what kind of car is that?

btw what kind of car is that?

A shot in the dark here but I'm going to guess one with 4 wheels, a motor, and a couple of doors...

not a side car? damn, im wrong again

No factory amp. It's a 2001 M3. Will try your suggestions tillithz and get back to you. Thanks. Any role for a noise suppressor?

a noise suppressor is just a band aid for the real problem, and not only will it suppress the hiss, but the entire sound spectrum which you probably dont want.

OK thanks for the info.

tillithz, do you NOT have any hiss?

I removed my factory setup (head unit, all speakers and sub) and used an external amp. All professionally installed. All new wires, no factory re-use.

I did retain my factory rear DVD setup that plays both audio and video to the Z1. I get hiss all the time. I'm betting this is the cause of my hiss...

I have an appointment Saturday to have the system rechecked and to add the iPod controller.

Any thoughts as to what to have the installer pay close attention too? This will be his 3rd attempt at removing hiss. I think he put a filter on before but it didn't help very much, if at all.

Thanks!