Navigation instructions are disabled under certain conditions

[Jörgen]

I don't know if this is related to one of the new versions or if it's an old problem.

Here's what happened today: I connected my Sena 30k headset to my iPhone as the first phone. The second phone connected is the Oukitel RT3 tablet (with MRA for navigation).
Everything works very well so far.
But when I establish a Bluetooth connection to my freind, I can no longer hear the navigation instructions.
At first, I thought, OK, the Sena headset can't connect to three Bluetooth devices.
But then I received a warning from my speed camera app.
This means that the BT connection from the Oukitel tablet is active after all.
So why are no navigation instructions coming from MRA?
When we later reached a via point, it was announced by MRA without any problems.
The question now is, why does MRA differentiate between a via point announcement and a navigation instruction? Why are via point announcet and turn instructions not?

Do these announcements have a different priority in the Bluetooth protocol?

When I cancel the connection to my friend everything works fine.