power inverter noise

Heres the problem. I have a 400 watt power inverter hooked up in my car ( powered with 4 guage, directly to battery)I'm using an adapter with a 3.5mm end, and the other end is a set of male Rca plugs, anyways, its all tied into the IP bus on my Pioneer head unit. Whenever i have my laptop plugged into the power inverter and, the audio side plugged into the head unit i get some nasty noise through the speakers ( only when plugged into the inverter) Thought about using a ground loop isolator, but i'm not sure if this would work. Also, i do have a 4 channel amp, and a mono block in the car. Anybody got any ideas?

Thanks, mike

What I wold do is get a DC-to-DC converter, I got one off of ebay for $20 or so, it can be switched from 12v up to 20 volts...it also comes with an assortment of different plugs so you can use it with other things.

now, if you want to keep your inverter, I would try using an in-line power filter.  My guess is that the inverter is picking up the alternator noise, making it part of the electricity going to your laptop thus making the electricity to your laptop noisy.  this noise is part of the sound signal sent to the headunit so an loop isolator wouldnt work.

IF you are not using a pure sine wave inverter(most people dont, they use a modified sine wave inverter), there will probably b noise in the sound anyways.  so what I would do is just use a DC-to-DC converter on your laptop