The problem just occurred recently. I've had this headset for a while now and I've been having this problem for weeks, for some reason it also detects it as a USB Speaker and sometimes needs to re-download the device driver.
I've already downloaded the Steelseries engine and updated it but it still hasn't fixed it.
Update: It got worse so I finally decided to reformat my PC, it has stopped the crackling but it might come back so I reinstalled the Steelseries Engine, only problem is it doesn't recognize it as a headphone, it recognizes it as USB Speakers.