Originally Posted by SinSere
As you said, the video is fine, so the head unit and brain are most likely good. If only the sound is having issues, I would imagine its something with the stock amp that you are talking about. Especially if you're getting it when hitting bumps, a connection has to be loose.
You checked the back of the head unit and think its all good there, have you checked all of them at the amp and brain?
Shitty deal because its hard to trouble-shoot something if its only having problems when you're hitting bumps. It may take a while, but I would go through all the RCA connections and speaker connections to the amp and brain. If ALL speakers have the static, not just one or two, it would have to be an RCA issue, not a speaker wire issue.