Good questions....I haven't gone to the store yet, tomorrow I think. I'll be sure to update here with any changes.
I went to Apple today about all this. They could not recreate the problem and since it has only happened to me once (the only LONG phone call I've had so far), they just tested a few things, said my phone was perfect, and sent me on my way. They told me I might have been holding the iPhone at a strange angle & the sensor went crazy for a bit. I don't know, they just told me if it happens again and continuously, to bring it back.
I'm definitely having the issue. I've tried all the reset fixes with no positive results. I've trained myself to hold the phone away from my face enough to not cause any issues but the problem is definitely annoying. Hope Apple can come up with a software fix soon.
Discovered the source of my problem - I had installed a "skinit" cover on my phone. They provide a graphic cover for both the front and back of the phone - both static sticker type with graphics of your choice. The front comes in two pieces - one both the top and bottom of the screen. The top section has three holes - one for the front camera, one for the ear piece, and a third that I could not determine what it was for. I initially left it in because it looked better for my graphic. Turns out that's where the proximity sensor is. I removed it and now the sensor is working fine. Not really sure if the resets fixes I tried had any impact at all. I would say that any covering over the proximity sensor - including a plastic screen protector - would block the sensor and cause the issue. I don't recall having this issue ever with my 3G and I had a screen protector on it about 90% of the two years I used it. Seems like the Apple engineers have made some pretty big mistake on the technical design of this version of the phone. I still love the better features and performance but wish it was a cleaner implementation.
On launch day I reset my phone's settings and it seemingly fixed the proximity sensor issue. But today it reared it's ugly head again. I wished Apple would stop worrying about the jailbreak developers and release an update already.
its hardware all the way just like the antenna issue where MOST ppl thought was software and its not! the sensor was probably half assed on some devices when they finished the i4
If you noticed on the white demo model there was a cutout where the proximity sensors are to allow the light through. I'm guessing they didn't think they needed it on the black but it looks like they do.
My guess is the bezel's too dark to allow enough light to penetrate through to the sensor and therefore it can't determine the difference in light levels when pushed to your face and doesn't turn off.
I had the issue and promptly went to apple. The guy at the genius bar took some sort of microscope thing stuck in the headphones port and looked inside. I mentioned to him, jokingly, "there is no water damage i'm sure" and he replied "i'm not looking for that." After about 30 seconds he put the phone down and told me they would replace it. Two days later I now have my brand new iphone 4 again and the issue seems to have been resolved.
