Before you go through all that work, I would go into the audio set up of SAC. Choose a diffent driver type, anthing but ASIO. Save your default prefs. Restart SAC and then put it back to the ASIO settings for your RME card (I'm assuming your sig is your current set up). That has cleared up messes for me in the past.

Also try just deleting the prefs file for SAC all together from your SAC install folder. You will have to restore all of your settings but that can fix things like this as well sometimes.