Previously owned a Samsung Galaxy S9 and my auto bluetooth system worked as expected. I started the car and it auto-connected for taking calls and playing music.

Since changing to Pixel 7 and Graphene OS I have wierd bluetooth issues. I can pair and connect to the car audio but when I restart the car (after original pairing) it does not autoconnect. It also has issues when I try to manually connect. It works after a few tries. Car is 2014 Subaru Outback.
All of my other bluetooth devices have no problem.

After searching the forums I saw one issue may be the avrcp version. I have tried downgrading avrcp to 1.4 which matches the version on my Galaxy S9. It does not seem to help.

Any suggestions would be appreciated.

    I couldnt find a match in the recent issues (since the bluetooth stack was changed).
    I played with it today and I am able to initiate the connection from the car audio manually. Previously I was initiating from the phone where it fails to connect until I restart the bluetooth system on the car.

    Interested to know if any subaru owners have similar issues.

      My family vehicles are a F-150 and a Renegade. Neither has any issues with using GrapheneOS for bluetooth phone or music connections. Set than up once, and as long as the vehicle batter is not disconnected, like when you change a battery out, or the battery is removed because you have to get to something in the engine compartment that is underneath, everything just works.

      3 months later

      driekus Yes. my 1999 Impreza but I have a Jensen stereo 2017 model that I have to put the code in every time I start the car. I can turn BT off but it comes back on by itself. I even can change the code but it doesn't stick. I can still use the OEM code of 5309. I even unhooked the battery until Pixel 5 didn't show up under "devices" . That it does hang onto that info tells me it has power or working backup battery that I see no way of replacing. The main point being I have a 2014 Mercedes that has no issues at all. And I think before I installed Graphene the Jensen didn't either. So I just don't get the difference.

      a year later

      Same with my pixel 7. Neither my Sony headsets nor my car (Seat Leon 2017) connect automatically. I must connect manually.