has anyone taken off the sliding bar tension grippers and either roughed them up a bit or changed the angle they come together. My problem is that certain strings, like Prince Recoil and Pro Supex Maxim Touch start sliding toward the top of the gripper, and will pop out. I've cleaned them with alcohol. Apparently, they tighten from the bottom to the top, which forces the string upward in the gripper, to the point that the string sticks out just out of the gripper. A good cleaning allows about 10 pulls before I have to do it again. My 1st gen Wise doesn't do this. Don't know why my Gen 2 version does this.