Lots of good information here. My ENV3 just developed this same problem (sound only when flipped open). Before I start down the path of disassembling my phone, I'm wondering if someone can tell me just how deep you need to get to try to fix this problem. Since the instructions are for replacing the screen (and my screen is working fine), I'm wondering how far I need to take my phone apart to get to the foil tape mentioned by Bob or the spring contacts mentioned by rickdp1. Incidentally, for me the the problem was intermittent at first and then became permanent, which makes me suspect some sort of a bad contact. Any help will be greatly appreciated!