Here's the problem:
I took my 2007 F150 5.4 in for warranty work. There was a rattling, crackling noise, which almost sounded like engine rattle, but didn't change when the engine speed changed. The dealer told me it was bad fuel, which I disagreed. They insisted that was the problem and suggested changing fuel or the station where I purchased the fuel. Funny, that my 2005, with the same engine size never made that noise. Anyway, a few weeks after picking up my truck from the dealer, I turned the key on, without starting the engine and there was the noise. Now, tell me it's bad fuel. The sound seems to be coming from around the CD Player. Its not a continuous noise, only every once in a while. Has anyone else had this problem?

 

If it’s the 6 disk unit then it’s just cycling through the cd’s, I don’t know why, but it randomly does that on startup. Mine does it a couple times a week.

 

Sorry, it's not that.. This is a crackling noise. Some kind of electrical shorting kind of noise. I know what it sounds like when it's cycling.

Thanks anyway.