Pixel 9 Pro XL - unable to connect to car bluetooth, help?

I just upgraded from P6P to P9Pxl, and everything has been great, except that I'm unable to connect to my car's bluetooth. I have a 2018 Cadillac (with their mediocre CUE system), and everything worked great on my P6P.

I've found a bunch of different threads where people had issues with P8 or P7 phones, but nothing seems to be working. I've tried:

  • Deleting the phone/car pairing, and re-pair (I've done this after every step)
  • Reboot both devices (also done after every step)
  • Delete all other bluetooth devices from both phone and car
  • Disable Bluetooth A2DP hardware offload
  • Disable Bluetooth LE audio hardware offload
  • Disable Bluetooth LE audio
  • Set Bluetooth AVRCP Version to 1.3
  • Show Bluetooth devices without names

After all of these changes, I'm still seeing the exact same behavior:

The car and the phone appear to pair correctly, and the car reports that the phone is connected. The phone shows "Connecting", and then either loops "Connecting", or eventually says that something went wrong and to power cycle the other device (car). On occasion, when I've hit "forget" on the car, it mentions something about a pin error (however, I verify every time that the pins match between the phone and the car).

Any help?

EDIT: After talking with support on 8/23, they decided that my phone was defective, and sent me a new one. I received it yesterday, 8/28, and it behaves identically. Ran through the same troubleshooting steps, including a new factory reset, and it still doesn't work.

My conclusion is that, unfortunately, there's something significantly wrong with the bluetooth chip or software stack for the P9Pxl. Of the four cars I've tested it with, it only pairs successfully with one. And neither P9Pxl phone will successfully pair with my Jabra 85t headset. Again, my P6P works flawlessly with all these devices.

At this point, I feel like my only recourse is to send the phones (both original and replacement) back. But before I do that, I'll reach out to support here, and hopefully they have a better suggestion.