I've found that the latest firmware; 1.0.8 doesn't work correctly with iPhone 11 pro and BMW 1250 GS TFT that's also connected to BMW (Garmin) Nav 6. I can make a call that connects but there's no ringing sound or voice when answered. Before I found this I tried everything, i've become an expert on pairing and clearing the phone, nav, tft and 50R, I've done it literally 100"s of times, nothing fixed it. Until I realised that I'd used the wifi adapter to charge it just before it started doing this. not thinking that just charging it would cause a problem. But it had automatically updated to 1.0.8. Once I downgraded the firmware back to 1.0.6 everything is now working as it should. Thankfully SENA gives the function to downgrade through the App. Hope this helps others with the same problem. It took me 2 months to find.
50r No phone call sound! = firmware 1.0.8 issue.