Seems related to whatever I had to do to fix the other issue I had. I didn't notice it as much at first, but somehow, whatever I've done since then has made it more prominent. I would say every 5 minutes for me. The thing is that it's not only the lag and the ghost strokes, it's also the cursor will vibrate in a horizontal line (with sometimes ghost touches when touch is re-activated) that last for tens of seconds. I have found that lifting up the monitor from tablet mode will stop it. After that point, I'll just move it back down and continue working. It seems to happen less and less as time passes, thankfully. But that means I have to endure the strange cursor behavior during after I've woken it up from sleep/restart. I'm wondering if there's some sort of interference with the screen and something else when it's in tablet mode. I only seem to recall it happening then, so I'll try to test it out when I get home. I just don't know why this sort of stuff happens at all, really.