data field ascent / descent is freezing / not refreshing (only by button)

On my new 945 LTE, the ascent / descent related data fields (total, lap,...) are not refreshing instantaneously.
Often they are freezing and I can only see actual values by switching data pages.
All other data fields like hr, absolute altitude, vertical speed, distance, ... are refreshing instantaneously.

Any thougthts? Watch or SW failure?
Does anyone notice this.
Thanks.