300w Amp Engine interference

**sam1990rhodes** · 03-20-2011, 09:46 AM

Good afternoon,

When trying to run audio through the amp and video on the VM70 touch screen there is a terrible interference that is worsened when i turn the engine on, This only happens when both amp and screen are on together, seperatley they work fine, im not sure wether this is a grounding issue as as ive said they work perfectly sepereatley in the car.

im half expecting someone to say just use one at a time

any help would be apprecaited. excuse me if im beign dumb.

**OldSpark** · 03-21-2011, 02:29 AM

I'd start with the grounding.

**soundman98** · 03-21-2011, 05:18 PM

Originally Posted by OldSpark

I'd start with the grounding.

+1

to expand a bit on the idea-- many times a poorly connected ground--either a dirty connection, or loose connection, or multiple grounding points for multiple pieces can cause the problems your describing. they are very common in car audio installs. i suggest you search a little for 'Ground Loop'. there is tons of info on what can cause them, and how to fix them around here..