Okay let me put you out of your Oculus misery. Your cable and headset is fine.
The problem you're seeing is caused by the headset demanding more power than the USB bus of your system can give. I had this issue and ended up getting three replacement headsets sent. Save yourself the inconvenience and get a mains powered USB 3.0 hub. I picked one up on ebay and has fixed my DP-port/USB port disconnection nonsense.