SW or HW fail with latest Garmin OHR - cross country skiing

Ive now tested both Garmin 945 and Garmin Venu and the last generation OHR on the Fenix 5X. Both the Venu and 945 fail on OHR for three different people when cross country skiing. The OHR is little less than half compared to HR strap, so completely useless.

The Fenix 5X works great and is +- 5 from HR strap for all three of us. Thats the same result for three different people with different skin tone no mather where we place it on the arm. Something is messed up on latest OHR from Garmin when doing sports where you hold something in your hand in cold weather. SW or HW? 

Has anyone tried cold weather cross country skiing or paddle on the 945 or latest generation garmin OHR? Same results?