Very poor showing from the headset range

Ok i first started out with the v1500 they broke one side stopping outputting sound so i rma'd them which was very quick had my replacement in less than a week. I was given an upgrade to the v2000 model and in less than a month the headset started to buzz and hiss. So started an rma again. This took nearly 2 weeks to get my replacement. So 3rd set arrived i was upgraded again to the v2100 which i thought was nice. Less than a week after i got them they have developed the same fault buzzing whilst the mic is in the on position (buzzes worse whilst charging with the mic in the on position).

I have requested another rma over a week ago there has been no reply at all. has the customer service team all gone on holiday?

has anyone else had this issue with buzzing?