Flashing black lines in some apps

I just got a new laptop (Toshiba Satellite C850) that came with Windows 7 pre-installed so I decided to get windows 8 Pro at the discounted price. I downloaded it and so far I love it. However, one thing I noticed was that when I am using some downloaded apps (Shazam, Khan Academy, etc...) these crooked, horizontal black lines appear at the top of the screen every once and a while and almost make the screen shake. I don't know what is causing this but it is getting annoying. Any help is greatly appreciated. Thanks

It has even started to be thick white/grey flashes in the middle of the screen aswell