Did a full reinstall of GSX.
Now I have no audio...
A GSX reinstall surely cannot affect how your audio drivers supports ( or not ) OpenAL, which is the only requirement for GSX audio to work. Sometimes the audio drivers don't initialize in time, so you might just try to restart Couatl, and see if they appear.
If they never work, regardless how many times you try, it's possible you audio drivers don't support OpenAL, so you need to either update them, or try different drivers, sometimes the manufacturer drivers works better, sometime it's the opposite and default Windows drivers works better.
Also, GSX doesn't support audio devices that can be plugged out dynamically, like USB audio cards. That doesn't mean you can't use them, but they need to be active *before* you start GSX, if you plug the audio device after you start GSX, you'll have to restart it to have it available in GSX. None of this will ever require restarting the simulator.