Companion Save Battery - Blank Screen / Heart Rate Drop

Hello,

I run Zwift on Apple TV and I use the companion app as a Bluetooth bridge to connect Zwift Play controllers, Wahoo Kickr Core, Giant Ride Sense cadence, Garmin Fenix 6X pro Heart rate. At the same time I run Shox Open move on bluetooth to my phone for music. Generally everything works reasonably well but… for some reason heart rate occassionally drops. This happens with Garmin Fenix 6X pro and Wahoo Tickr. Garmin seems to behave better in general. The heart rate drop is more frequent if the companion app is not “active” on the screen. If I put the phone in “black screen” mode with Companion running in the background to save battery, everything works but the heart rate drops more frequently. So… I want to keep the app open to have fewer heart rate drops but that “eats” phone battery. I don’t need companion active because I can do everything from the Zwift Play controllers.

So…does anyone know how one can have a blank screen but have Companion “fully active” behind the black screen & or - does anyone know something specific about heart rate drops. (It is always the heart rate - never any one of the other bluetooth connections!)

Thanks

Adrian