Hi Dave,
Another test flight this time using default A320neo without the FlyByWire enhancement mod. Noticed even with the default A320 PF3 does not tune radios but I got PF3 ATC right up until climb to cruising altitude instruction and then nothing.
I continued with flight and PF3 paused sim at destination as I had previously configured.
After flight I checked and even the default FS2020 ATC does not tune radios on the A320neo default. So I do not believe the radio functionaility has been added to this aircraft and something else is going on here unrelated to what the radio frequencies are set to.
And in previous flights PF3 has worked for me right up until the point it pauses the sim.
logs attached
Regards