said by Xaak :

Carren,

What version of BOINC are you running?

There seems to be some issues with hybernation and suspend modes, where boinc's internal timers get messed up, or from using time servers which will automatically adjust your system clock to match a reference clock. But it seems that this is only on older versions of BOINC. I can't find any reference to wu problems causing this, but you never know.