For many years when the end section of the pole starts to slip and tightening the clamp doesn't help I have assumed the problem lies with the fact that the section has worn at the end where the clamp tightens. I recently watched a youtube video on how to change phoenix clamps which suggests the wear could be on the clamp instead of the pole section. Changing clamps is clearly much cheaper but imo if the problem was the clamp, the section would slip no matter where the clamp was tightened rather than just at the end. Any thoughts.......