Maybe you have better eyes than I do, but I never saw anybody say anything about rattling. Try to stick to the subject/question at hand, instead of adding additional complications that wasn't asked in the 1st place please.
ORIGINAL: xd9x19
If you're referring to the "rattling" issue when the mag is loaded with 13 rounds, then my XD9 mags sometimes do the same thing when fully loaded, but don't when it's at full capacity-1. Not an issue as far as functioning.