Could anyone explain what's going on? (Audio problem)

Okay so I need to export a video for an animated collab I'm a part of. I've followed the tutorials on downloading a ffmpeg and exporting the whole shebang. But I've run into a problem that I'm not sure is with Krita or my computer. There is audio both before and after the scene I'm animating, and I dont know how to crop it out of the animation. But when I render the animation, it includes audio that picks up before my scene, throwing my whole animation out of sync. I've tried exporting using the exact frames it starts and ends with and the same problem occurs. I don't know what to do or how to fix this and the animation is due soon! Please help! Thank you.