Still using buttons and icons disappear or move

[CADMama]

OK - I have one guy that I work with that is still using buttons on AutoCAD 2013 with Windows 7. (I know, I can't help it either!)
His icons seem to disappear on him or else move around. The ones in the layer dialog box showed up as the dimension ones.
WTH - I have not customized ACAD is no long I can't fathom what the problem is. Any ideas?

[dgorsman]

These aren't customizable. Could be a corrupt install, or bad graphics driver, or maaaaybe somebody was diddling with the DLLs e.g. copying a DLL from 2008 Mechanical to 2010 AutoCAD MEP.