Hi,
I have been experiencing the same problems myself with the h8's. I just recently received the h8's and was really looking forward to them as they were my first experience with a product from B&O. Unfortunately while using bluetooth they drop out constantly to the point where they are unusable. I am running them with a mac pro 2013 (with built in bluetooth 4.0). I was previously using harman/kardon bt headphones for over a year and never experienced any bluetooth related problems. As such I did not even think it would be an issue with B&O, but am certain the problem lies with the bluetooth of the h8 headphones. I would have expected this to not even have been an issue from a company with a reputation for such high quality, especially when others have obviously figured it out with no problems. While they work great with the auxiliary cord connected, bluetooth was important to me which is why I choose the h8's. For $500 and my first time trying a B&O product, I don't think nearly as highly of the product/company as I had previously had. I am very disappointed.