All of my XDm mags rattle when fully loaded w/ 19 rounds. Even with the +10% Wolf mag springs. But I do have to move it pretty good to get them to make noise.
But take it apart, clean it and see what happens as mentioned above.
And for the record, you have a magazine, not a clip.
Years ago the recommended fix for mag rattle in the KelTec P11 was to disassemble the mag, remove the follower, and then slightly bend the top spring loop "up" a tad. I tried it on both of my rattling P11 mags and it worked like a charm.
I suggest that you (And others who may read this) attempt the same thing with their mag springs. Don't go crazy with your bending or you'll create a weak spot in the spring. Just open it up a bit at a time - reassemble and check it. Do it again if you need to .