I took my mac pro in yesterday to fix a memory issue. They took the computer in the back so I couldn't see what they were doing. Before going there the startup sound would come on fine. Now when I brought it home, I hear no startup sound at all when I boot my MP. It passes POST fine so I know that's not the issue. What could be wrong? Could there be a cable somewhere on the mobo they forgot to connect? Any help would be appreciated.