[SOLVED] Volume buttons of Suunto Sonic did not change FP4 global volume, until paired with a Mac

Hi, it is not a request for help, but just an unexplained resolution of a problem I had (and that could help other people).

4 months ago, I bought a Suunto Sonic (a Bluetooth headset). Bad surprise: the volume buttons did not change the global volume of the phone, but a volume related to the headset. So the resulting volume was something like “GLOBAL_VOLUME x HEADSET_VOLUME“. So if the global volume of the phone was low, there was no way I could make it louder with the headset (annoying when the phone is in a bag).

I tried several things:

  • In dev mode of the phone, enabled AVRCP 1.6 and disable (and re-enable) the Absolute Volume, restart both (cf message)
  • Unpair and pair again the headset.
  • Use it on my previous phone (Samsung A5 2017: it worked as expected)
  • Resetting the headset (plug it to power cable and keep the multipurpose button pressed for a few seconds).

Nice surprise: after pairing the headset to a MacBook Pro (for which the volume buttons worked as expected), it started to work properly with the Fairphone 4. I can not explain it. But given this experience, if someone has the same issue, I suggest trying to pair it with some other devices to see if it resolve it for the FP4.