xrandr trouble with nvidia settings

I want to configure my monitor Setup automatically via Script using xrandr. It works once, but if I attache my docking station again (Lenovo T520) the following error occurs. If i reconfig my monitor setup with nvidia-settings in some way (it does not matter how) the script is running properly again.

Can somebody help me with this?

I’m using arch linux with nvidia 331.49-1 and xorg-xrandr 1.4.1-1.

Here the commands I use and the error message:

xrandr --verbose  --output DP-0 --off   --output DP-3 --off   --output DP-4 --off   --output DP-5 --off   --output LVDS-0 --off   --output VGA-0 --off 

crtc 0: disable
xrandr: Configure crtc 0 failed
crtc 0: disable
crtc 1: disable
screen 0: revert                                                                     
crtc 0: revert                                                                       
crtc 1: revert        

xrandr --verbose --output DP-1 --auto   --output DP-2 --auto --right-of DP-1

xrandr: cannot find crtc for output DP-2

Thanks
Jakob