I have a 2015 RT-S that has developed an irritating squeak when you hit a washboard or rough section of road. I thought I had found the issue in the LH mirror, You could make it squeak by moving it by hand. Took it off, adjusted the clips, even greased the posts and it seemed fixed but noise was still there. Took both mirrors off and noise is still there. Sounds like it is up front and doesn't seem to do it if you hit something square with both tires but always does it if the bumps are sharp and uneven. Sprayed WD-40 on every bushing and sway bar but no change. Has anyone else had the issue and what was it?