Unexplained Periodic Losing of Focus

I've been experiencing an issue for a few weeks now...

It seems that at every 10 minutes after the hour (e.g. 1:00, 1:10, 1:20, etc.) whatever application I'm using loses focus, causing fullscreen applications to minimize, and causing me to have to click in order to keep typing. This only happens on regular desktop-mode applications (which consist of over 99% of what I use), and I don't notice any issues with the "Metro" apps.

From what I've seen, most people claim that this is an issue with an anti-virus application, or some other application putting up notifications in the notification area. However, looking at the notification area I see no notifications pop up when when this happens.

I have AVG AntiVirus Free, and I scan with the free version of Malwarebytes Anti-Malware every-so-often.

Based on several scan from both of these applications since the problem has arisen, I do not appear to have a virus or a problem with malware.

Thanks.

UPDATE:
Actually, it seems that the "10 minutes past the hour" thing was a coincidence. This still seems to always happen at 10 minute intervals, but I it doesn't necessarily happen at 1:10, 1:20, etc.

UPDATE 2:
Sometimes doesn't happen at 10 minute intervals (can be as short as 3 minute intervals), but always stays regular until restart.

I seem to have found the culprit: TeamViewer.

Unfortunately, I wasn't able to directly determine this. I had to go through a long process of exiting out of things one at a time, then going back into a game, to fix it.

From my understanding, a vast number of applications can cause this as well. I can only guess that there is some operation that many applications perform that causes this issue.

Again, back to having this issue, even with TeamViewer closed. Can't seem to figure out why this happens so often.