Your location, antenna, etc may have something to do with quality of audio.
I believe that at the current time TPD is simucast on the analog site. I also hear Tulsa county on both sides. Tulsa fire is P25 only.
I have the same radio. I set the digital agc on. I set the multi-site to stationary.
I set the Threshold high and low about 10 lower than default.
I'm on Keystone Lake and get good reception most of the time.
Welcome to the world of digital. Find a real good antenna and try different placement. Yes the Tulsa site is simulcast like the analog but with digital it's either receive a clear signal or receive nothing at all.