I echo Mike's idea. I did that for my PRO-197 and PRO-106 using Win500, and get Arlington just fine.
My only other idea, is make sure that you are not mixing the older frequencies, talkgroups, or other settings from the old system with the new P25 system.
Feel free to bounce ideas off of me if you want. I don't speak "Uniden", but the settings ought to be the same for both brands of radios (although maybe inputted differently)