Yes, I noticed the same issue even in stock aircraft. For example in stock C172 in 2024, when you press the trim key on the keyboard or joystick button, the trim switch in the cockpit animates twice, and you can hear the click sound twice too.
This is because in 2024 there is a pause between the first and subsequent trim events, much like when you type something in notepad and hold the key down, there’s a pause between the first and subsequent letters (autorepeat). So it may be related to how the sim handles the WM_KEYDOWN events from Windows.
There was no such pause in 2020, the events were transmitted every frame as long as the trim key was held down.
@EPellissier this is posted under 2020 bug reports, but it’s a bug in 2024.