PokerTracker

I just would like to know if anyone has similar problems:
I have a Quadcore Q6600 and PT3 seems to be the first program I`ve ever seen only using one of the cores !
So Core 1 runs at 100%, Core 2,3,4 only at 20%.
Never seen that before.
Any ideas ?

Does this happen only with the Hud in use?

No, it happened while I was datamining 16 tables.
After I closed them and started to play at 4 tables, everything worked fine.
Well it`s not thaaat terrible anyway and I´m sure you have other things to do, but it`s strange.