Yesterday I could do a parallel test using Version 5.20 on the oregon.
As you can see the behaviour with the Garmin Cadence 2 is better than with the old one. So there must be a dependency with the sensor hardware.
The sensor is connected to the Fenix and the Oregon using ANT+. As far as I can see the Oregon supports bluetooth, but primary only for the communication with a smartphone.
But there are still segments where the cadence isn't zero where it should be.
Fenix:
fenix.png
Oregon:
oregon.png
Maybe one can make a comparison between the Fenix and an Edge? It could be that the measurement
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