Yeah used to happen to me every so often. Also say for example you needed three points to win a division from two games and you were winning and the other person quit, it would end the season instead of letting you play the last game.
Forgot to add it would also not count as a win and you would still be in the same division
Many people have said it could be something to do with the wiring.
Been reading this about fifa but it might have already been posted. http://fifaaddiction.com/fifa-issues/lag-fix/