I have tested more than 20 white iPhone 4 (ALL WITHOUT SCREEN PROTECTOR AND CASE) and all have proximity sensor problem. Im curious about white iPhone 4S. For those of you who received your white iPhone 4S, can you do the following test? And this is how you can recreate the problem: 1. Make a call with speaker. 2. When the call is answered, turn the speaker off and place the phone to ur ears. Does the screen turn off when the iPhone is by ur ear? Cheers!