I’ve got the Thrustmaster TPR pedals. I guess it could be but the fact the aircraft is registering a positive GS suggests it’s more a bug in the sim of some sort, possibly brought about by the add-ons maybe.
It’s so wierd; I can apply the brakes while apparently frozen, which immediately causes the GS to go to zero. And then, come off the brakes, apply thrust, GS appears to increase but the plane doesn’t actually move through the scenery.