I noticed the OSD speaker was overly large when using Metacity Compositing. Turning the enhanced effects off put everything back to normal. I do not use Compiz, so I cannot verify it does the same thing there. This narrows down where the size issue lies, so if anyone has any further suggestions, please share.
Currently running in the computer lab:
Linux Mint 17.2 MATE
Linux Mint 17.2 Cinnamon
CentOS 7 GNOME
Debian 8 LXDE