I get regular upticks in stroke rate while using my watch during rowing activities. It has started about 2 months ago and I cannot figure out why it is doing it. the upticks are regular and the same magnitude. They are not natural and not associated with my rowing during the activitiy - they are regular and significant jumps in stroke rate and i and my crewmates would notice if this was actually happening. I recently upgraded to fenix 7s from forerunner 735 and it is still doing it. What could be wrong? I am not sure how to upload a picture of an activity graph here.