AlarmKit custom sounds are universally broken in iOS 26.0 stable - instead of playing your custom sound, it plays a system error/timeout beep. I've spent days investigating why custom sounds result in what sounds like an error beep (like when you cancel an operation or hit a timeout) instead of the actual audio file. I can now prove this is an Apple bug, not implementation error. Evidence: Test 1: My Implementation Followed Apple's documentation exactly Tried both bundle and Library/Sounds (as documented) Result: System error beep (not my audio) Test 2: Professional Apps Tested ADHDAlarms (popular AlarmKit example by jacobsapps) https://github.com/jacobsapps/ADHDAlarms Their airhorn.mp3 custom sound: same error beep (not an airhorn) Their default sound: works perfectly Test 3: Device Testing Physical iPhone (iOS 26.0 - 23A341): broken iOS Simulator: broken Not device-specific Files are found correctly, but the actual audio file is never played. Instead, you hear what sounds like a system error/cancellation tone. What I've Eliminated Not a Library/Sounds vs Bundle issue (both broken) Not a file format issue (.mp3, .caf, .m4a all broken) Not an implementation issue (professional apps broken too) Not a device issue (simulator and device both broken) Not a file size issue (5KB to 2MB all broken) The Documentation Lie: Apple's docs for AlertConfiguration.AlertSound.named(_:) state: "Choose a file that's in your app's main bundle or the Library/Sounds folder" https://developer.apple.com/documentation/activitykit/alertconfiguration/alertsound/named(_:) Both locations are broken. Tested on: iOS 26.0 (23A341), Xcode 26.0.1, Swift 6.2 Impact: This affects any app trying to: Provide personalized wake-up sounds Use custom alarm tones Create meditation/sleep apps Differentiate from default iOS alarms Current Status: Multiple bug reports filed: FB19900024, FB18237648, FB19779004 Apple engineer claimed "fixed in latest beta" in August Still broken in iOS 26.0 stable (September) Workaround: None that I know of. You must use .default sound. For apps needing custom audio, play it with AVAudioPlayer after the alarm fires and user opens the app. Question: Has ANYONE gotten custom AlarmKit sounds working in iOS 26.0 stable? If so, plzzz help I'd be so grateful.