Itunes Radio stops/starts intermittently

Recently, itunes radio has been stopping & starting intermittently. This happens on both my iphone 5s and my home PC. It happens with both "My Stations" and "Featured Stations". It happens when other wifi-related tasks are working fine. Whenever itunes radio is running on my iphone, a swirling circular icon appears next to the wifi signal icon, as if there is something being downloaded that causes the stoppage. Older versions of this problem appear at other places in the forum, but there has never been a clear solution posted. Other than Pandora ...