Shane,
I am having this problem with rundll32.exe. In the first shot you can see the speaker icon in the system tray. When I right click it to bring up sound options, it will not show up (I use this to switch to digital output so i can listen to music through house speaker system) on monitor but rundll32.exe is present in task manager (Shot2). If I open another window of a different program it will show (not immediately thought, almost like it needs a kick start). This only happens after my system has been running longer than a hour or so. I have run windows repair (reset registry and file permissions, register system files and repair exe association), ran avast and malwarebytes (full scans). Before all of this I ran check file system and system file check. I don't know where to go from here. Can you help?
Chris