I have permanent tinnitus (ringing of the ear) in my left ear from shooting clays...anyway, I want to get the telex 850 but the noise reduction is 12 db. where as passive is much more like 23 db. Is there any way to put additional ear cups to seal out the noise (make it passive reduction as well)? The ear cups only go on the outside of the ear thats why there is no passive reduction. Any ideas please!