Can't install package for AudioKit on Xcode 14.1, in Monterey.
It is asking for credentials and there is no choice for unsigned packages.
Followed these instructions:
Using Xcode, you can add AudioKit and any of the other AudioKit libraries using Collections
Select File -> Add Packages... Click the + icon on the bottom left of the Collections sidebar on the left. Choose Add Swift Package Collection from the pop-up menu. In the Add Package Collection dialog box, enter https://swiftpackageindex.com/AudioKit/collection.json as the URL and click the "Load" button. It will warn you that the collection is not signed, but it is fine, click "Add Unsigned Collection". Now you can add any of the AudioKit Swift Packages you need and read about what they do, right from within Xcode.
Try to add package as per the instructions. It's asking for credentials.
It's because you are using the wrong feature to add the collection. To reproduce your issue, I enter the AudioKit Swift Package COLLECTION url in the PACKAGE url search bar in the top right, which is intuitive but wrong. The collection thing is different than the package thing.
The correct method is to use the little "+" sign in the bottom left to "Add Swift Package Collection" and then paste that AudioKit URL into the link. Your walkthrough goes back on the rails after that.
Here is a link to where/what it looks like. If you mark this post as answered StackOverflow might finally let me post embedded images so you don't have to click the link.