Simple Keyboard Commands Stop Working?

So this started recently. For some reason that is not apparent to me, some simple key commands will just randomly stop working in PS2. For instance it won't let me alt-tab, hitting any keystroke such as enter to start chat, tab to see leaderboard, U to redeploy, just stops working. Oddly things like R to reload and the weapon keys 1-X work fine. What is the deal? Anyone else have this issue? PC specs are in my sig. I haven't changed anything.

It happen for me randomly that entire keyboard stop working while playing planetside 2.

To add to this, it only becomes an issue in full screen mode, other modes seem unaffected...