Forum users on Microsoft.com and WPCentral have been gathering examples in an attempt to narrow down the problem, but with limited success. Those discussion threads have already hundreds of comments, and are joined by those at Nokia where users report similar problems. Though it's certainly not hitting every Windows Phone 8 device it's annoying those it does hit.
Support staff from the three companies have reportedly been suggesting rebooting and booting the phone without a SIM card for ten minutes."
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