How do I record audio only from specific window?

[danbntx]

Using Debut Pro I'm recording Video and Audio from a specific window (playback of a webinar). I park this activity on a second monitor and go about my regular activities so when I want to watch a news clip or something else in a different window on different monitor... Is there a way I can make sure Debut is only recording the audio from the original intended source, and not pick up audio from my general web browsing? Thanks!