So this problem is exclusive to russian medium and heavy bombers for some reason.
RPM-control (increase/decrease) is simply not responding in any way.
Even if I use it with a HOTAS (both HAT switch and buttons, I have no free axis to assign it to/try it on), on my keyboard with custom bindings, or keyboard with default bindings.
Which of course means I have no way of flying IL-2's or Pe-2's. Super frustrating, to say the least.
Just to be clear - the keybindings USED to work just fine just a couple of weeks ago. The problem started maybe a month ago, so I assume after a patch was released or something.
For reference, I use a cheap Thrustmaster Flight Hotas X Flightstick. And yes - the same keybindings work just fine for any other aircraft.