I have a galaxy S3 and am finding people cannot call me when the phone is not active / awake. If the screen is active / on, people can call me without any problem. If I have NOT been using the phone for say 15 minutes (phone is on but screen is not) my phone never receives calls. As soon as I wake-up the phone, I am able to receive call without any problem. Anyone else encountering this problem? Any ideas other than keeping the screen on all of the time. I am wondering if this has something to do with ice cream sandwich and how it handles multitasking.