I got an email last week from Paul detailing how he was having problems with his T-Mobile 8320 and his Jawbone bluetooth headset. It turns out that when he made calls over UMA while on Bluetooth he would drop the call. This did not happen with his old Jawbone but only with the new Jawbone that was just released.
Paul then learned that UMA, WiFi, & Bluetooth all run on the 2.4 GHz band which may interfere with each other. T-Mobile even told him that there is no workaround for UMA and some Bluetooth headsets.
I know some people using the hacked (dd-wrt) Linksys firmware on their wireless networks have gotten a new feature called Bluetooth Coexistent mode which fixes this issue.
Has anybody else found a workaround? Are you also experiencing this issue? Feel free to help Paul out in the comments…