I often use my Wacom One to draw pitch bends, but I’ve found that sometimes the cursor doesn’t update its position when I’m using the tablet pen. The cursor looks like it’s moved with the pen, but when I press down the piano roll scrolls up or to the side and I have to move and click with my actual mouse to update the position. When I move or click with the mouse, the cursor snaps back to a different position than it was in with the pen.
This could be down to the settings on the Wacom. I have one too and had this issue where pressing with the pen started to scroll down. I can’t think off hand what I had to change in the settings, but it doesn’t do it anymore.