SOLVED: This cable or accessory is not certified and may not work reliably
Since iOS 7.0.2 was released I was plagued with this message NUMEROUS times a day WHEN NOTHING WAS CONNECTED! I had tried all the tricks like resets, restores, recovery mode, dfu mode, Apple replacements and STILL had the problem! I discovered it was indeed foriegn material in the data port of my iphone. But it was by design. I have a bodyglove shocksuit which has a cover that goes over the port and has a tab that inserts INTO the port to keep it "protected". Well that turned out to be what was causing this message on my original iphone 5 and 2 new replacements. After a trip to the apple store it was pointed out there were physical contacts that the case was triggering thus making the phone think there was a cable or accessory connected. Since there obviously was no real electronics this woud cause iOS to throw that error message thoughout the day as introduced with 7.0.2. Since then I cut that tab off on my case and for two weeks now I have not seen that message. The only downside is that little cover over the port doesn't stay closed anymore. I've contacted Bodyglove(Fellowes) to see if they have had any issues like this and it seems I'm the first.