Welcome to the forum!

I can not explain why the exported audio uses different sounds than Finale’s playback.

As a workaround you can use Audacity to capture the Finale playback audio.

Since you mention aif, I will assume you are on a Mac. Other than that, there's too much we don't know. Please take a look at this:

https://makemusic.zendesk.com/hc/en-us/community/posts/215729367-General-Discussion-House-Rules 

Mike - I have seen the House Rules before. Didn’t think I was in violation, but I see that I failed to say it’s a Mac IOS. I don’t see anything else that I failed to include. If you’d like to ask me more please do, as I would sincerely like to know how to control the output sounds. 

There's no "violation". We're a Users support board trying to help other users. My post was aimed at trying to eliminate the guessing game.

By IOS, do you mean Apple Silicon such as the M1? What operating system? This stuff is important—I already know you are on a Mac. You'll see that the regulars have this information in our signatures. You can edit your MakeMusic account to add that to yours, too.

I can tell you that there are issues exporting to .wav in 25/26/27 but that doesn't explain what's going on with .aif so that's unlikely to be the problem. Other than that, without more information, none of us are going to have a clue.

We do need to know the exact steps you are taking because this is not a common complaint. Feel free to post screen shots (Command Shift 4, hold your mouse button down to draw a box around what you want us to see, release the button) if that will help.

Mike -

Sorry. You're catching the limits of my tech brain. I should have typed MacOS, not IOS. (Don't know what an Apple Silicon is!) I'm on MacOS High Sierra. I'll go back and add those pieces to my account. I'm finishing this project before I update to Finale 27. I've been working with a deadline that is critical (this Friday). The last phase was to create audio files of each choir member's part, so they could have a secondary learning source. 

Since posting my question, I've learned how to work around it, so I don't really need any further assistance. Mr. Thomsen's solution, adding another piece of software, might have solved it too, but you already know my tech limits! Finale has always been my Notation software (Finale 98 and beyond), but haven't used audio & midi with it until this project required it. I like being forced to learn new things, but the software's random patch-switching when I exported to WAV, MP3, or AIFF was baffling. And no language in the manual explaining it. 

Thanks for your guidance in the Forum. I appreciate your patience with me.

No problem. I create guide tracks for my choir, too.

Since posting my question, I've learned how to work around it, so I don't really need any further assistance

That's great!