The Xbox headset head band could do with a few more botches, I’m at the maximum and it’s just about fit around my head to go over my ears. This doesn’t happen with my sennheisers or Sony or others.
I had the same problem. Really disappointing. I was quite happy with everything apart from the fit. I wound up returning it. Just going to use my Razer Opus via the included 3.5mm cable for now as they sound excellent and fit well (and not even on max extension).
I had the exact same issue with the Xbox One Stereo Headset too. It's like nobody on Microsoft's design team has a large head