Cadence double counted

Dear fellow Garmin people! 

I have a Fenix 5x and an IPhone and a pair og Jabra Active EarPods. 

normally I don’t run with music or anything so my phone is at home. But sometimes on especially long runs or some walks, I like listening to a podcast. But when I have my phone in my pocket and running or walking and tracking the workout on my watch, it’s like double counting steps. So for example. Today I ran with jabras in the ear and phone in my pocket (on running tights) and my avg cadence was 266! The same happened days ago on a walk, the cadence was above 200! 

Is it my phone or might the Jabras somehow? Any one tried this and maybe knows the fix? 

- Morten