Yesterday I began hearing a sound about every minute that I assume is some kind of alert or notification that something needs attention but I can't determine what it is. It sounds like a single pick of a guitar string. I recently downloaded an upgrade to microsoft office but can't recall if it began right after that or not. I sure would appreciate any suggestions you may have...I have done the restart etc...but being new to a mac I am at a loss as to what else to look for. Thanks in advance for any help al