Chart going slowly backwards by itself

Hello,

like said in the title, when I draw something and then delete it with backspace button, a few minutes later, the chart automatically starts going slowly backwards for one deviation of a ful chart size. This started today. I also noticed that youtube videos tend to not start immediately sometime - also started today - like they start for a milisecond and restart, so it's like a very quick stutter until I refresh the page. I added a secondary monitor with VGA to DVI adapter and that's all I changed.

Hope it helps, thank you.