I am scheduling critical user notifications with a custom sound. This worked for years both on devices and in the simulator. Since Xcode 26 it crashes in simulator. Example let content = UNMutableNotificationContent() content.title = "Critical" content.body = "Example" content.sound = UNNotificationSound.criticalSoundNamed(UNNotificationSoundName("notification.aiff"), withAudioVolume: 0.5) content.interruptionLevel = .critical let trigger = UNTimeIntervalNotificationTrigger(timeInterval: 10, repeats: false) let request = UNNotificationRequest(identifier: "exampleCriticalNotification", content: content, trigger: trigger) UNUserNotificationCenter.current().add(request) It seems that simpler variants such as just content.interuptionLevel = .critical or just content.sound = UNNotificationSound.defaultCritical also crash. I assume that critical notifications is a small niche use case but i still hope this gets fixed. This is filed as FB20272392 with a full crash log.