When it catches, does it do it in exactly the same place on the hone, and does it do it every time or only sometimes? If so there may be a piece of grit embedded in the stone.

If it only happens sometimes then the hone may be hitting a rough patch on the blade, or the blade may be hitting a particularly suction-y patch of the hone. Or the hone could be catching on a wired part of the edge and tearing it off.