Bad video "clipping?"

I play on xbox and if I switch between my stash and vendors too many times sometimes my screen will be filled with grey/yellow grid boxes and 50% of the time my character will disappear but I am still able to control it. If I can manage to find a waypoint or an exit of the town area I am in I can "reset" the graphics and when I go back everything is back to normal. This has happened during different acts and only happens to me when I am in a "town".