Trunksu

Ok i've had my GC (Ground Controls) for more than a year now but recently i had decided to lower my ride even more. But ever since I decided to lower it some more, the right front passenger side spring is making a vibrating noise? I can't hear it if i have music playing. I'm not sure how to describe the noise because I had originally thought it was metal rubbing metal, but the shop told me it's not. I guess i'm hearing the springs bounce a lot?

The shop told me it's very normal especially the lower you get. So trying to ease my fears I've decided to get advice from everyone here. I have Tokicos in the front with the GCs. Thanks for any advice/opinions.