Question Why does my Garmin G3X and G5 show 38 mph when not in motion?

[Neal]

Went to my maintenance shop today for a few inspections including the 24 month transponder cert. The guy asked why my airspeed was reading what it was when not in motion and I never really paid attention to it as it seems to work fine for flight, etc. What are others seeing on theirs and if you have any suggestions what may be going on with mine let me know. The tech alluded to it may be a setting somewhere.

 

[Cactus Charlie]

My IAS on ground and not in motion is as shown below. I see see non zero IAS during run up which is due to poor static port position but I have come to accept that.