I have owned this headset for a short time and am basically very satisfied with it. However, I have noticed two points that are annoying: 1. the battery lasts at approx. 20% volume, 33% LED and without Mic. approx. 5-6 hours. I find this very short. Are these values normal? 2) I constantly hear a very low hissing/whirring noise from the headset. At first I thought it was a noise and tried different USB ports. To no avail. Interestingly, the noise is even louder with a cable connection. Does anyone have similar experience? Personally, I expect absolute perfection from headphones in this price segment. My Astro A50, which is getting on in years, has a massively better battery life with 0 noise...