Note that I use the two rocker switches on my yoke for adjusting trim, as indicated by the yellow arrows in the photo of my yoke. Left rocker is used for elevator trim up/down and right rocker is used for rudder trim left/right. So I use no axis settings for adjusting trim, just these rocker/button presses, which worked fine until either SU4 or SU5. Before that time, a quick press and release of the trim rockers would result in minute changes to attitude. But since SU4 and SU5, including the latest world update, just tapping the rocker results in terrible fluctuations in attitude and altitude.
For instance, I recently took a flight with the C152, and after about 10 minutes, had it cruising fairly level at about 9,000 ft, RPMs about 2100, speed about 95 knots. The VSI was showing a very slight climb rate of about 5ft/min. I tapped the rocker on my yoke to add a tiny bit of trim down, and the VSI within a few seconds was showing a negative 1605ft/min descent, with the speed rapidly increasing. This was almost immediately followed by the plane pitching up into a nearly 600ft/min climb, and sudden decrease in speed of course. This yo-yoing continued for about 45 seconds, until the plane was in almost level flight again.
This is what happens anytime I try to trim the plane at all, which is ludicrous. And note that the same thing happens if I use the default keyboard commands of Num 1 or Num 7 to try and adjust the trim, so the issue is not unique to my contoller. The sim is just responding crazily to any input.