Can I just swap out audio and re-render without any degradation?

I know this may be a stupid question, but I am just starting to know how to use FCP. I just want to swap out the audio on a completed video for a slightly enhanced version of the audio. Of course, I know HOW to do this, so that is not the question. The question is about any loss of quality.

Can I just make a new project, swap the audio and re-render the video without any degradation of quality as long as all the settings are the same as the original project? Since this is digital editing there should be no loss of quality if I keep re-rendering the same video right?

Yes to all of that.

Thank you kindly. Okay, that's great and easy then. I'll go ahead.