Hello @McDin, thank you for the feedback.
I would like to fix this. Can you please share your crash identifier? I think the app may be crashing in the background. See: Crash identifier
The disco mode on Windows only supports Microphone input at this time. I am planning to add more options like system audio (speaker output) in a future update. Lots of features are still under development as noted on the upgrade screen. The Windows app was just released a few weeks ago.
Let me know if you have any questions.