System clock (or display) keeps freezing.

My clock display (menu bar) keeps freezing (stopping/not advancing) after a random amount of uptime (couple of hours to a week). For instance it will say 4:01:25 AM and not change until I click on it and it will update to current time (and stay/freeze at current time). Sometimes it will update from screen saver wake, top of the hour or when I open a program (but freezes again).

I have tried:
1) Reinstalling ML
2) System Preferences: Date & Time: unchecking/rechecking Show date and time in menu bar
3) Changing from analog to digital and all the display options

 

Just did a time check at Time.is and my system clock is only -0.0006 off. However my display is "stuck" and won't advance.Is there any know way to for the display to update very second so it will display the time normally.

If no way to get the system display clock to work is there a good App that will install a working clod in the Menu Bar?