Hi Anders,
Normally, this setting should be stored in the .ncrunchsolution.user file (which is where NCrunch itself will put it), but it doesn't actually have to be. It's possible for it to be hand-coded into any of the solution or global settings files.
I would suggest a full configuration reset. Your global config files are stored in C:\Users\[USER]\AppData\Roaming\NCrunch. Make sure the IDE is fully closed and the engine is shut down before removing or renaming any of the settings files. When all the solution and global files are gone, the settings should fully revert to default.