Game time error

[blind-eddie]

I have been running an arcade site for a very long time and have questioned the time a member played a game to achieve the high score on many occasions.
Members reported irregular game times on a few games played by other members.
I would play a few games to see what kind of time I would get for comparison and have banned a few from my findings.
Then, a few minutes ago I tied the score to this game but, did not take top spot due to their time being better then mine.
I tried the game again and only went 17 seconds and the game was over and I was sent to the scores page as usual but this time it moved me to top spot for my 17 second time which was not correct.

How can I fix this from happening again on my site?

Edit: Tested the time on my site on the same game in which I took top spot with a better score, time was not a matter in it but, I let the game run for 16 seconds and the scores page showed my 16 second time as my time on my earlier score.