I am having the same issue... I select "engage max thrust reverse" (or similar) in the X-Plane buttons' selection and assign a button to my throttle box. The reverse levers engage but no I do not hear the thrust reverse. When I tried, I was landing at a speed of 117 Knots and perhaps by the time I tried engaging the reverse my speed was too low(?) Could this be the issue? I then tried landing at a higher speed (135 Knots) but I got the same result (thrust levers go up, but the thrust will not engage). Does anyone know what I might be missing? thanks