Configuring Voice Quality of Service for Skype for Business Online IP Phones

Markus_Johansson - the 40 value default is an old relic...literally from the Lync Server 2010 days....but it's a confusion as a result of the differences in definition between Precedence Level values and Class Selector values.  See Jeff Schertz's blog for a good explanation on this:

http://blog.schertz.name/2011/08/lync-qos-behavior/

Lastly, as I said before, DSCP for video is not specified anywhere in the server/tenant configuration.  It will NOT be marked by default so you will not see anything on your client if you are taking WireShark traces.  You have to manually configure QoS in Active Directory Group Policy (which then gets assigned to computers) or configure class-maps on your network switches to mark the traffic to the desired DSCP value for your video streams.  Only after you have done that will you see any video streams marked with the appropriate DSCP value (assuming your network infrastructure doesn't strip it along the way).