Why have no-one been able to get a proper qos for adsl. I understand the complexity of the technology and it relying on so many variables,... but.. with all the technology available today, surely there should be some light at the end of the tunnel.
if your router support qos (most routers do), you can set which protocol/application has higher/lower priority. if not, you can use traffic shaping software like cfosspeed.
some router will even let you specify minimum bandwidth for certain protocol/application, which will guarantee you enough bit rate.