Difference of timing pc and pb108

Hi,
I am testing trial version with ninco pb 1.08 version. Everything good, I like it, but... there is a small difference of seconds (at the end of the race) between the total time of PCLP program and total time of pb (partials are perfect). I believe it is something coonected with the start process; my questions, if enyone had the same issue:;
1) which is the right timing?
2) how do you think that is possible to allineate both the timing?

Thank you,

Francesco