OK, so there is a noisy section of audio I want to delete but the video in that section is OK. I only want to delete the audio section. All I could figure out to do was lower the gain in that section. I hope I can get some advice. Thank you.
Cut the audio each side of the offending area then delete it. But make sure you activate the "Ignore Event Grouping" button on the bottom toolbar first so the video isn't affected.
Probably you're alrady done: but just a production note, it's gonna sound very odd if suddenly you have no sound at all. A better way is to copy and fade in/out a "silent" section from somewhere or just lower the volume of the section till the noise is, well, just background noise.