Parts of this have been the subject of posts on this form and others, but not in its entirey: I successfuly pair a BT headset with the 4S and make calls with no problems Randomly, the 4S drops the BT connection and reverts to speakerphone Randomly, I dial the phone without BT and it only allows me to use it on speakerphone Randomly, I dial a number and hear nothing This has happened with TWO different BT headsets - Jawbone and Plantronics. None of these problems has occurred while listening to music on iPad. Is Apple issuing a software upgrade to address this? I don't recall anything of this happening before the upgrade to 5.01 or whatever it's called. Thanks.