Stuttering in FH4 when I upshift/downshift with my paddle shifter on my wheel?

So I plugged in my CSR Elite and Pedals to FH4 for the first time yesterday. I usually play on controller on my laptop, but figured I’d give it the proper treatment with the wheel on the big machine (despite many nightmarish threads warning about wheel support).

Something happened that I’ve never seen before. I play at 120 Hz at 1440p, and every time I shifted up with the right paddle of my wheel, my framerate would drop down 10-15 FPS for a fraction of a second, creating an amazingly irritating “stuttering” effect. The same is true when downshifting- it will stutter the game if I’m moving more than 10 MPH, in any car, upshifting or downshifting. This does not happen with a controller or M+KB, just the wheel.

Has anyone else had this problem? Is there a solution? It’s so annoying that I’m seriously considering not using the wheel anymore, despite it being an obviously superior experience.

To be clear, this is the only racing game where this happens. I tested F1 2020 and iRacing shortly after, with zero problems in either game. Game Mode has been toggled off and on, no effect.

This might be the silliest bug in a racing game I’ve ever seen.

Thanks for any help in advance.