Intermittent noise

Alright, first off everything installed was NIB.  Head unit is Sony CDX-F7705, front speakers are running off amp and are polk db-6500, rear speakers are running off deck.  Sub is JL 12W04 running off bridged rear channels of amp.  Amp is Soundstream Van Gogh 500.4.  On the amp the power light is on but the rca light that should be on is only on intermittently.  According to Soundstream I have a problem with the deck.  According to Sony they think it's in the amp.  I do know that the setup worked well for several hours and then suddenly developed noise that was coming through the amp.  I swapped out rcas with new wires and noise was still there.  I swapped out head units and noise went away.  Now it gets weird.  I reconnected the head unit that had the issue and there is no noise.  I'm sure it's probably only a matter of time until it comes back but I can't find the noise if it's not there.  I do know that the rca open light should be illuminated when switched to the "sense" position and it is not.  Everything is working for now, but I wanted to know if anyone else has had  a problem with this head unit or with the new soundstream product line.  I knew I was taking a chance with soundstream because I've heard their quality has gone down since being bought out, but I was stubborn and had to find out for myself.  Oh, and the noise should not have been caused from the engine or altinator because the noise was the same with the engine off as it was running.  Any suggestions will be greatly appreciated.

Sony head units are notorious for many kinds of problems.  They simply are not built very well.  Who knows, it could have been oxidation on an RCA connector that is fixed now... but I suspect your problem is likely to return.Support the12volt.com

I was leaning towards the head unit myself.  I have not been very impressed with it.  I should have stuck with the brands I was used to instead of using one of my vehicles to try out new products.  I also noticed that sony did not do a very good job with shock absorbtion, anything more than a minor bump in the road and the cd will skip.  Granted the truck doesn't ride the smoothest buy come on, I've never had a pioneer skip on me and I've beat the hell out of those radios.  They seem to be inexpensive but I can't complain about them for the price.  I wish I had one over this sony now.