Stefanl, there are 2 screws holding the anti-skating housing to the base. It sounds like yours are loose. This happened to me, and it is a relatively easy fix. The hard part is to find the screws! They are normally covered with plastic plugs and blend into the surrounding area so they can be hard to find.
I used an exacto knife to pry mine out. Unfortunately, I damaged one of the plugs and have not put them back in, but it is cosmetic problem only, and a very small one at that.
See the picture at the link below: http://s93813957.onlinehome.us/mediac/400_0/media/16016.jpg
One of the screws is visible just above and to the left of the "Basis" decal. (my arm is oem basis rb-300). The oher screw is to the back and right, on a diagonal from the other.
Thanks again to garth for helping me figure out my problem.
I used an exacto knife to pry mine out. Unfortunately, I damaged one of the plugs and have not put them back in, but it is cosmetic problem only, and a very small one at that.
See the picture at the link below: http://s93813957.onlinehome.us/mediac/400_0/media/16016.jpg
One of the screws is visible just above and to the left of the "Basis" decal. (my arm is oem basis rb-300). The oher screw is to the back and right, on a diagonal from the other.
Thanks again to garth for helping me figure out my problem.