Hi galeair.
I had exactly the same problem. But I found a way round it. I am on P3D 4.5 and also have Honeycomb Bravo throttles. First, with the throttles resting on the latches, left mouse click on the latch. Then, either using Bravo or mouse move the throttle lever a fraction of an inch off the stop and back to the stop then right click the lever. Or you can make the (past idle position of the Bravo) an engine fuel cut off function. Sorry it's so late, but only just read your post.
John Caselton