hi when i change playback device or output fxsound crashes everytime i uninstalled it and didnt worked update didnt worked.
edit : if you have my problem too , easily go to sound settings and disable every playback device your Not using and leave what you want to use as enabled then open fxsound again and it work without crashing and you can re-enable your disabled playback devices again it worked for me i hope it works for you as well!