Can't init SDL No available video device

[sous.studio]

Trying to install libxext-dev:

libxext-dev : Depends: libxext6 (= 2:1.3.3-1) but 2:1.3.3-1netrunner1 is to be installed
E: Unmet dependencies. Try ‘apt-get -f install’ with no packages (or specify a solution).

It seems to me I must somehow disable netrunner repository for this to work. Or maybe upload libxext-dev to netrunner repo? It seems it was there in 15-updates version?