Fireball7d7Sounds like a resolution issue that's pushing everything to the second monitor.
I use this program to lock my mouse to my first monitor when tabbed in. I had issues where when the game stuttered and I was flicking my mouse would go to my second monitor and tab me out. You can set up this program to attach to the tf2 exe so every time you launch it locks the cursor.
i'll try this!
i also think its weird that this started to happen out of nowhere.. could it be due to my monitor being broken? my monitor cable that goes into socket input makes weird tiny but high pitched noise basically 24/7, until i unplug it then its fine for a day