Standing sizzling

Tired of stereo headphones I bought this helmet signed corsair after the many positive test of this vengeance in 1500.
Unpacking OK, I try the helmet: a bit heavy but no more, shakes a bit at first but relaxes relatively quickly (it was less tight after 3 days of normal use).
I was somewhat skeptical about the USB connector which for me does not really represent the world of sound, but essential to power the sound card built-in volume controller that heats much moreover.

So I connect, I will install the driver (only available on the site corsair) and lenfile on the head. I immediately sends a film in 5.1 with virtual 7.1 enabled. Excellent first impression: very good Spatialisation, you really believed in the film.
I then cut the film and there: sizzling! While I listen to absolutely nothing. A sizzling continues, not very strong but troublesome in the long run. And when the volume drops below a certain threshold (relatively high) means the sizzle. We even feel that at times the sound is not clear, due to sizzle. I tried everything: change the USB port, I tried 4 different PC, always the same story!

This helmet would have been great if he had not this defect MAJOR. I did not want to return to Corsair, lest he refers me another one with the same defect. Besides the highly recurrent problem of the whistle as soon as you activate the software using the microphone (Skype, TS).
So I finally decided to take another headset, the Sharkoon X-Static Pro 5.1. Certainly, two times more expensive but it is a real 5.1 and Sharkoon is a brand japprécie for these helmets.

First time I'm disappointed Corsair hopefully the last.