Hi. I spoke with Apple support and we tried a lot of different options including a complete reset. The issue continued where it would loose contact with the speakers after 10-15 mins and just continue the sound volume. You could not change it. Also, when the unit is put to sleep it would lose connection with the speakers as you would expect. However when the Apple TV was woken up you would have to go back to Bluetooth and reconnect. The whole scenario would then start again where you would loose Bluetooth control of the sound after 10-15 mins.
The initial diagnosis from tech support was that the unit must be faulty and I have a genius appointment booked. However I tried it on a separate Apple TV. I have both the 4K versions and the HD version and even after a reset on both, ALL Apple TV’s are doing the same thing. I have paired the speakers to my Samsung TV and that works fine.
My initial conclusion is that for some reason the Apple TV’s don’t like to work with these speakers which neither Apple or the speaker manufacturer can work out. My only other option is to change the speaker for a WiFi version that uses airplay 2 and try that.
I am open to all options here so feel free to comment. Thanks for all the help so far.