Possible bug - stuck air speed

[MiRexer]

First flight in the Caravan I think I ran into a bug. My airspeed got stuck around 150 knots. I think it happened when I adjusted the true airspeed dial on the airspeed indicator. I noticed it in my descent that my airspeed wasn't changing and REALLY noticed it on approach. It affected both the pilot and copilots air speed indicators as well as the air speed indications on the GTN750 density altitude page. I flew the approach and landing using the ground speed indication on the GPS. Checked on the tablet and none of the covers were in place and no failures shown on the failure page. I have it on video if you'd like me to upload so you can see.

[jasmits]

Pitot heat on if conditions required?

[MiRexer]

Yes Pitot heat and stall heat were on as well

[jmarkows]

Did you tap the glass?

[MiRexer]

No didn't think of that but shouldn't that only affect one gauge?

[MiRexer]

https://www.youtube.com/watch?v=HzxKlDrQTNU - I didn't mention the pitot heat but you can see that it's on here.

[AK Flyer]

I just had the speed max out at 150kt on decent. Descended through 2000ft and it jumped up to the correct speed. I didn't touch the TAS adjustment during the flight. I'm using the TDS GTN if that matters

[MiRexer]

FYI - I'm using the PMS GTN