Bluetooth connection issues (Android Auto) - Xiaomi Poco F1 Questions & Answers

Issue:
When connecting to Android Auto (wired, USB C, cable works with other phone, so is good), Spotify audio plays, but drops a second every 3 seconds. Bluetooth audio seems to have connection issues.
After I've tried all of this, it also seems that the F1 seems to be less responsive (e.g. finger print works very slow and unlock is slow in general).
Same issue also occurs on other music player. So issue doesn't seem to be with Spotify.
What Ive tried:
Connected a different phone (S9) with no connection issues.
Connected another Poco F1 (stock ROM) with no connection issues.
Bluetooth audio to a headset is not an issue (tried a Sony and a Bluedio set), no drops on Spotify audio.
Tried the latest version of PE+ A11. Dropped every 10 seconds.
Also tried A11 rom Arrow OS. This seems to have the same issue in AA - dropped every 30 seconds.
PixelUI A12 has the same issue.
Awaken OS A12 has the same issue.
LOS A11 does not hae this issue.
Details:
I am using PE Android 12 rom, but had the same issues with PE+ A11 rom.
What options do I still have? The A12 rom was installed "clean". Formatted up front.

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This still seems to be an issue for my phone.
A11 LOS does not have this issue, the bluetooth seems to be stable and sound is not having issues.
On A11 PE and all recent A12 Roms the BT connection is having issues.
When connected and I would play sound, it plays the sound for a couple of seconds, after which it drops the connection, sound plays on the phone, and reconnects BT, then plays over the speakers of the car again for a few seconds and drops over to the phone again.
I've tried resetting the car audio installation, did not help.
I've tried resetting the BT on the phone, no change.
What options do I still have? Was there a recent change into A12 on the BT connection?
Options currently testing: Disable BT A2DP hardware offload. BT AVRCP Version set to 1.6.

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Further checked, and eventually found that my Poco F1's Bluetooth has issues. While the other Poco F1 which I have in the house, does not. Is there a way to reset the bluetooth in general, maybe via a stock rom, firmware or vendor (all 3 already tried, but just want to make sure). Not sure how this issue can occur, bluetooth did not have any issues before the last update of A11 PE, since then, all sort of issues occur with the phone.