Randomly occurring short-term artifacts

Hey guys,

I suffer from randomly occurring artifacts that last for 1 or 2 seconds. However, I can not reproduce them and therefore, I dont know where they come from. Could this be a hardware-failure? I attached a picture. The artifacts are not app relevant, but mostly occur at this place. Whatsoever, sometimes they show up at different places too. Furthermore, the colors, as well as the patterns are not the same every time. Sadly I ran out of warranty just one month before.

http://www.imagebanana.com/view/69vbrok4...

Thank you in advance!

Best regards