Bluetooth reconnection fails with ATH-M50xBT2

Lethiks

Hi,
I'm using a Pixel 8 Pro running GrapheneOS (build 2025041100) with an Audio-Technica ATH-M50xBT2 Bluetooth headset.
Every time I turn the headphones off and on again, I get the following message when attempting to reconnect:

For security reasons, forget this device and pair it again.

This happens consistently after every power cycle of the headphones.

What I’ve already tried:

Fully resetting Bluetooth on the phone via Settings > System > Reset > Reset Wi-Fi & Bluetooth.
Factory-resetting the headphones (holding Volume + and Volume - until I hear “Bluetooth settings cleared”).
Multiple clean pairing attempts.
Verified that the MAC address of the headphones does not change between sessions.
Tried setting: adb shell settings put secure bluetooth_bond_state_persistence 1 but didn't do anything and since the default value was at null I suspected it was disabled by GOS.

Is this behavior expected due to GrapheneOS's strict Bluetooth bonding policy?
Is there any way to persistently authorize a trusted Bluetooth device to reconnect without having to pair it again every time?

Thanks in advance.

de0u

Lethiks Every time I turn the headphones off and on again, I get the following message when attempting to reconnect:

For security reasons, forget this device and pair it again.

I have never had that happen while using multiple Bluetooth headsets (Pioneer, AKG) and also multiple cars.

In addition, searching online for that message turned up zero hits aside from this forum thread. That is very odd. Is that the exact text of the message?

Lethiks

de0u
It's not the exact message it's a translation from the following french message, since my phone is in french.

Pour des raisons de sécurité, oubliez cet appreil, puis associez-le de nouveau

Here is the message in English if I switch system language to English (UK) :

For your security, forget this device, then pair it again

teezeh
There is a companion app for my headset and I already installed it but it doesn't fix the problem.
It might be due to the fact that the ATH-M50xBT2 can be paired to 2 bluetooth device and play sound from the two of them simultaneously but I rested all pairing in the headset and only paired my phone and the problem still occurs.

teezeh

I use both Pixel Buds Pro 2 and Technics EAH-AZ100 with my GOS P9P and do not experience this issue. So I would assume it is specific to your Audio Technica headset. Does AT offer a companion app? Maybe that could fix it?

Lethiks

With the true English message instead of my translation of it a search return a post recently made on reddit about a month ago of it occurring with a Garmin smartwatch and an unnamed audio device on a Pixel 9 pro with Google stock OS. So it seems to not be exclusive to GrapheneOS.

de0u

Lethiks With the true English message instead of my translation of it a search return a post recently made on reddit about a month ago of it occurring with a Garmin smartwatch and an unnamed audio device on a Pixel 9 pro with Google stock OS.

Also there is an official Google support post: https://support.google.com/pixelphone/thread/338042726?hl=en&msgid=338065239

mmos

GrapheneOS release 2025-04-25, currently in the beta channel, contains a change that somehow might be related to the issue:

Bluetooth: backport upstream fixes for compatibility with certain Bluetooth peripherals caused by a recent security fix for Bluetooth encryption

Lethiks

mmos
I just updated to this version (2025042500) and the problem still occurring. From what I understand the problem is also still present on the stock Google OS and hasn't been fixed upstream either.