c016Y, Welcome to digital servo's. I had this problem and it was not the linkage. You want them as tight and slop free as you can get. The solution is to back off on the servo mounting screws, so the servo is utilizeing the rubber mount grommets. When driveing the screws in untill it bottoms out on the brass sleeves you are bypassing the isolation factor of the rubber. They are there for just this purpose. Also make sure the hole that the servo sits in is not too tight. I tried all kinds of changes on the linkage without relief. Went to "ask Danny" on the JR sub forum and problem solved. Good luck, Joe