Check the following:
1. Is the turntable level?
2. Is the Armboard level (when it is not original Micro Seiki)?
3. Is your adjustment right (Pivot to Spindle)
When that is all right, then you have a problem with your Arm
The 3012 can't handle all kind of cartridges, it is not really good in energy transfer (vibrations in its bearing), normally it runs well with ultra soft suspended cartridges...when nothing helps, go for a better Design, FR-64s. That Arm is a total different chapter.