In the old Conn and Lowrey organs, key clicking was caused by adhesive failure that allowed felt strips to move from their intended positions.
You must pull your Technics apart and see what the problem is. New felt is very cheap at the fabric store. Pick some up and cut it into strips. Use a modern glue that won't saturate the felt and won't fail in a few years. I would use Shoe-Goo for this
Jack, October 2011