Weird rattle in my new CM Storm Sirus headset

[feriluce]

So the cable of my old steelseries 5Hv2 gave out yet again, and I decided to finally replace it with a new headset.
To replace it I bought a CM Storm sirus headset, and while it seems to generally work pretty well, I've got one problem.
Whenever I turn up the master volume, or the base volume above a certain threshold, one of the drivers in my left ear starts rattling.

Does anyone know if I've actually got a faulty pair of headphones and need to return them?

 

[feriluce]

Done a bit more testing, and it seems to be the left center driver thats having some problems between about 60-200 hz. Still not entirely sure if its broken, or if I'm just doing something wrong.