Can't reproduce.
Maybe just image corruption that a \vid_restart would fix, or if it's only happening when you play offline then it's a custom or damaged PK3 file you'll have to remove.
The other possibilities are a custom hud with faults, or an error with gfx card drivers, so if the above doesn't help you fix it report your gpu/driver version.
Thanks for the help i will look into those. Imo its xsplit, whenever i start the game up while its running the ui gets bugged after joining a server and displays the character set of the game in front of the hud until i alt-enter out and go back to full screen.
It also seems to block screenshotjpeg and steam's own screenshot service while bugged. But as i sait ill check the pk3's once i get home.