Running Slow

The game runs perfectly smooth for the first half of the season, all the graphics are as they should be, yet as soon as I get past January, the match engine runs really slowly, to the point where a match that would normally last a few minutes at the most, is now taking 5-10 minutes. I have tried to limit all the graphic options etc, yet it is still not making any difference. Any help would be appreciated, because I really want to get back to playing it, but can't bear to with it like this.