My 2013 Outback developed an annoying rattle that appeared to be coming from the dash area to the right of the steering column. I could hear it when driving over slightly bumpy surfaces. I always like to use the sun visor and often swing it over to the side window and I usually don’t bother to snap it into its “locked” position. By chance, one day I snapped the visor in place while going over a bumpy surface and the rattle stopped! It appears that the bumps caused the two metal surfaces on the visor to hit each other and the sound must have bounced off of the dash. Now I always lock the visor into position.