I got a solution so I do not have to flip flop the hdmi channels from 7.1 to 5.1 (ore vise versa and back), followed this guide:
Have to add;
default-sample-rate = 6
in ~/config/pulse/daemon.conf
..also
If some one know how to configure both card to a main channel configuration, I would be glad.
I tried to do this in default.pa:
(for surround, hdmi)
load module-alsa-sink device=hw,3,0 module-combine channels=6 channel_map=front-left,front-right,rear-left,rear-right,front-center,lfe
(for two channel USB):
load module-alsa-sink device=hw,0,1 module-combine channels=2 channel_map=front-left,front-right
but that did not function.