Fenix 6 Bluetooth connection to Adidas Headphones Shut down

Hi dear Community and specialists. I am the proud owner  & user of my Garmin Fenix 6 Pro and since a few weeks also of the Adidas RPT 02 Sol Headphone. Made for sports.

I have noticed that the headphones always turn off after about 3-4 minutes after being turned on. This is particularly annoying while running.

However, this error only happens under the following circumstances: I pair the headphones with my Garmin Fenix ​​6 via Bluetooth ... as soon as a tracking / training program is running on the Garmin watch and music is playing at the same time ... then the headphones switch off as described above. It has to be restarted manually, after which it runs throughout the entire sports recording.

Any idea whats wrong? The Adidas support said I should go Garmin Support...but since i am a Beta user it may be reason of it's problem?

Cheers & Thank you

Tom