My left ear has developed a slight rattle and I investigated it and I have two pairs of these headphones and I took both apart to compare to see if something was wrong and all I could notice was this hard paste all over which is not on my second pair… what’s your thoughts on how to fix the rattle and what is the white shit all over my headphones 
! I’m assuming it’s a glue but it looks like shit !
Better late than never but it might be oxidyzation. It only seems to be on the metal screen or the driver magnet. Is it crusty like salt or solid like glue?