I would recommend you take a good look at the intercom.
Are you using a portable (battery powered) intercom or is it installed in teh aircraft?
I'm leaning towards interference problems with the intercom rather then the headset.
Active Noise Reduction (ANR) headsets generally don't work well with wind noise since they (at least Bose) has a little microphone on the outside of the earcup that picks up ambient noise which it then counters.
I always have a lot of noise in the Bose when I open the storm window.