2017~2022 CX-5 Radio interups NAV

Mazda, GT,
For no reason when using the NAV, my radio comes on and interferes with the NAV audio, Has this happened to anyone else?
Occupied Calif.
2019 CX 5 GT-R
I think the issue is that there is no way to turn off the audio system and still get the voice directions from the Nav system. On my 2019 I have found two solutions:

1. Get into the Settings menu and crank the volume for the Nav way up. That way if you are listening to the radio or music at a reasonable level you will be able to hear the voice directions above the sound of the music.

2. If you don't want any background sound at all and just want the Nav audio, select a source like USB or Aux that doesn't have anything connected to it. Then the steering wheel or console volume control will only be for the Nav sound.

At least I think that should work. I pretty much always have SiriusXM or music from a USB stick on when driving with some occasional AM radio for local news or talk shows.
2019 CX5 Reserve AWD
I'm pretty sure my audio mutes when the Nav speaks. I don't recall any problem hearing the Nav directions.
GA prior 16 CX5 GT
20 CX5 GT + Prem
I get nav audio from the left front speaker while the xm plays from the rest of the speakers, while nav is talking you can adjust the level of nav, when not talking you can adjust the level of xm...