Yeah, I too worded that badly.
It's not actually the timer that's inaccurate, once a timer is started it's pretty darned accurate.
It's in the setting of the timer where this occurs.
It's hard for me to explain what i mean, but it seems if its XXX ms before/after a whole second then the timer will fire that second earlier or later.
Once it is set though, the delaytime is accurate enough.