Is anybody else experiencing distortion / interference when making phone calls over UMA on BB 8520 OS 5.0.0.509? Calls seem to cut in and out. I deleted my profile, did a battery pull, and created a new profile for my wireless network. I've also restarted the router and switched channels (was on 6 now on channel 11.) I was not having this problem on the previous OS. Carrier is T-Mobile.