Unwanted Sounds occuring when switching workbooks

[btodres]

After installing PowerPivot I now get a ding sound when I switch between workbooks - even when Power Pivot not activated. I checked and the "Provide feedback with sound" in the options menu is NOT checked. Any help on this would be appreciated!

 

[Echo0]

Just thought I'd let y'all know that I began having the problem in Excel 2002 on Windows 7 about a month ago. I have no add-ins on Excel, and MySQL isn't on my system. The beep was not only occurring when I switched between workbooks, but also when I switched from, for example, Firefox back to my open Excel workbook. Something must have occurred during a Windows update, I think... anyway, I just took the simple route and turned off the default beep, because it was driving me bonkers.