Columbus P-1 Mark2 on Linux and Mac gets enabled for short and switches off again.

Hi there, I am new here so hello everyone

I have a Columbus P-1 Mark2 GNSS Receiver and try to run this with OpenCPN (5.6.2) in a Linux (20.04.5 LTS (Focal Fossa)) and a Mac-Book-Pro (macOS 10.15.7 Catalina) System.

The Device is recognized in both Computers
Linux -> lsusb -> Bus 001 Device 004: ID 0485:5740 Nokia Monitors COLUMBUS P-1M2 GNSS Receiver Mode
Mac -> /dev/cu.usbmodem8BC9B73238331

If I create a new connection in OpenCPN and choose the device, the GPS Icon in OpenCPN turns green/green bars for a moment and turns into a red circle again after a short period of time.

When I try to connect, in the NEMA Debug Window in OpenCPN there appears an output like: <GREEN>16:20:02 (Serial:/dev/opencpn0) $GNRMC,162001.000,A,3939.27523,N,00742.37615,W,0.00,49.86,011122.0,M,,*58<0x0D><0x0A>

So it looks like the Software is communicating with the device.
Why is it allways closing the connection again? Annyone has a hint for me?

Thanx