Bluetooth in Car Ruined After iOS Update

Bluetooth and iPhone have been working together flawlessly for several years. After updating to iOS 15, my bluetooth speaker is garbled. It has nothing to do with where I am. Connects well. Calls rarely drop. People hear me fine and clear. I can't hear in coming conversations since too garbled. I have disconnected and deleted my phone and any other unused devices. I paired my phone as if it were new. Same result. I believe 100% the iPhone software is responsible. I have downloaded iOS 16. No changes.

Anyone else?

Thanks!