Weird Windows 8.1 bug

[CGurrell]

First off this doesn't happen all of the time, and can be fixed most of the time by restarting the PC once or twice. Basically, whenever I am running a fullscreen window (Netflix window, VLC Media player, games, YouTube etc) my PC will, after 5 mins or so, simply exit the fullscreen window and attempt to run a windowed version (Which works for everything except games). My PC has also (more recently) started to de-focus on a window for a second or so, followed by the beep windows 8.1 makes when you, e.g. change the volume in the mixer, which can result in missed keystrokes in text boxes.

This has been happening through 3 different GPUs (Integrated, GTX 650 and r9 280x) since i built my PC in January. I've posted on a couple of forums about this and never even had a reply, let alone a suggestion. Is this simply a bug in Windows 8.1 that can't be fixed?

Thanks guys

 

Chris

 

PC specs (Just in case)
Intel core i5-3470

Cooler Master Hyper 212 EVO
ASUS p8 h61mx-r2.0 (I know this is crappy lol but I'm not overclocking so it does the job)

Sapphire Dual-X r9 280x OC'd to 1180mhz core clock at 1.3v

WD Green 2TB HDD

XFX Pro Series 1250w PSU (Cheap PSU, more for future builds)

(SSD coming soon)