No matter which source, iphone, radio or tape (a tape adapter gives the least dropouts) - the sound goes from all good to "reduced" all of the sudden, the volume is basically is halved and the sound is tinny. Premium sound mind you.

Since this is source independent, there could be something wrong with the amp, or perhaps the head unit? Which connections should I check, or how much are new/used amps? It COULD be a loose connection somewhere.

Frrrustrating.

 

Does it ALWAYS start out good and then go to volume reduced and tinny? Do you ever turn it on and the volume is already reduced and tinny already?

 

From what I remember It could start out low, then get good, then get bad again etc.

 

I would suggest double checking that ground you added in the AI-AUX box and make sure you do not have a cold solder joint there. It should be bright and shiny (not grainy and dull).

 

It happens without it in the loop, I can disconnecting the cd-changer doens't change things. Loosing ground reduces the volume a lot more to ~inaudible.

 

Sounds like you have an intermittent connection.

Try some contact cleaner on the connectors first, because it is easy.

One of the more common weak points of circuit boards in automobiles is where the connectors solder to the printed circuit board due to the weight of the connector and the attached cables over time and vibration. I would be most suspicious of any connectors you 'disturbed' by plugging and uplugging equipment. If you are up to it, it is probably time for a close visual inspection of these connectors at the printed circuit boards for solder fractures or nearby printed circuit trace fractures under a magnifier.

Alternatvely, I think a member or two on the board might have a spare headunit. If they come forth, and can loan it to you, you can isolate whether it is the headunit or the amp.

 

Jikes.

Hmm, might anyone here have a spare amp too? Or buying it with a 30 day return option could also work

 

And on my way to and back from work today, all sources worked as they should. Weird (but good!)

 

that's gonna drive you nuts...