Update: the app was rejected again on 23 September with the same message. We have replaced the attachment in App Review Information with an updated document, asked App Review for a phone call in the Resolution Center, and will request an App Review appointment when the next registration window opens. Other apps built on radio-browser.info are available on the App Store today, among them Streamlets, Eter, Sound Salvation and Pladio. If App Review can say what documentation resolves 5.2.3 for an app of this kind, we will provide it. Submission ID 448bc0d6-d797-444b-934f-9f0d7c1a5a28.