I found out that if you have the Windows taskbar at the bottom of the screen everything works dandy, but if you have it on the left side of the screen like I do, at your first tabbing out of the game it gets stuck and pushes the fullscreen DoD to right. This bug stays active until the game is restarted or the taskbar is moved to the bottom. I experimented with this a bit and saw that this happens every time as long as the taskbar is on the side and not at the bottom of the screen.
I would like to confirm this bug. I run with my taskbar on top and it is exactly as described by echoMateria. Very frustrating...