Woodware Finger Guard Paper Trimmer

Does anyone have a Woodware Finger Guard Paper Trimmer? I received one as a christmas gift, and very chuffed I was with my present. Since arriving back home and making a few cards I have noticed that it cuts wonky! At first I thought it was just me not putting the paper in straight, but after a bit of playing around I have come to the conclusion that it is the trimmer as it always veers off a straight line in the same place....much to my dismay. Has anyone else had this problem and have you been able to fix it?? Many thanks for your help! x