I have this problem quite often myself - just now I was sitting at my desk with 5 bars of 3G and couldn't get online. Is this really an AT&T problem or is it a hardware issue? I turned airplane mode on and off and I was able to get online but I shouldn't have to do that. I had called Apple and AT&T about this issue and they recommended turning my phone off every day (I've never been told that before) and cleaning out my Safari history, cookies, etc. once a week or so. I really questioned the Safari thing because that should have no effect on the ability of other programs to access the internet. I shouldn't have to clear out my Safari history to use the Sirius/XM app - that makes no sense to me.