The hissing sibilance of the EX1000 is pretty annoying as presented in those non-vocal tracks. It's like someone experiencing nasal blockage who is trying to suck his nose for breath.
I hope this sibilance will subdue with time. Didn't remember experiencing this sibilance with its little brother EX600.
inner-fidelity mentioned on his review that the ex600s are more suitable for portables than the ex1000s because of this issue if i'm not mistaken..