Comment 28 for bug 1078068

I had the same problem with my Dell Latitude 5470 with Intel i7-6820HQ, Sky Lake (rev 07), running Ubuntu 15.10 (4.2.0-35-generic). I found a workaround by disabling Xvideo as suggested by Nikolay over at freedesktop in the post dated 2016-01-14 19:44:42 ( Simultaneouos incoming and outgoing video now works perfectly.