Yesterday, I dropped my iPhone 3G on concrete, causing some big cracks in the glass. For at least the first few hours, however, everything still seemed to be working fine. Now, however, I have been experiencing a weird audio problem that seems to be limited to the headphone jack. Specifically, whenever I try to listen to anything via headphones, only the background audio can be heard - no dialogue on TV shows and no lead vocals on music. Everything sounds fine when played via the iPhone's speaker. I have tried several different video/audio sources and several different pairs of headphones, so it definitely seems that the problem is with the headphone jack. It must have happened as a result of the drop, but I can't understand why it would have worked fine for several hours afterwards. The only other thing that has occurred with my iPhone recently is I had to do a restore a few days ago (prior to the fall), but I believe audio was working fine after that. And, again, audio sounds fine when played via the iPhone's speaker. Anyone know what could be causing this problem and how to solve it?