If you open up SimplyE, go to a library that has both ebooks and audiobooks, and do a search, the intention is that you search the 'All' entrypoint, which includes both ebooks and audiobooks.

However, at http://qa.circulation.librarysimplified.org/, the link goes to the 'Book' entrypoint.

<link href="http://qa.circulation.librarysimplified.org/NYNYPL/search/?entrypoint=Book" type="application/opensearchdescription+xml" rel="search"/>

This link is generated by LibraryAnnotator.annotate_feed, and it does this because it doesn't distinguish between "the current entrypoint is 'Book' because the patron explicitly selected it" and "the current entrypoint is 'Book' because we're at the top-level default and the patron hasn't made a choice yet".