Remove Enable DASH setting; make DASH a last-resort format

Drop the dashEnabled toggle and its plumbing. Stream auto-selection now
keeps DASH as a candidate but ranks it strictly below progressive and
HLS formats, so DASH is only chosen when it is the only format available
(including live-stream fallback after HLS). The manual quality selector
hides DASH entirely on iOS/tvOS/macOS. Reconciles BackendSwitcher, which
previously treated HLS/DASH equally, to use the same DASH-last ranking.

Yattee/Core/Settings/SettingsKey.swift

@@ -20,7 +20,6 @@ enum SettingsKey: String, CaseIterable {
     case cellularQuality
     case autoplay
     case backgroundPlayback
-    case dashEnabled
     case preferredAudioLanguage
     case preferredSubtitlesLanguage
     case resumeAction

Yattee/Core/Settings/SettingsManager+Playback.swift

@@ -70,19 +70,6 @@ extension SettingsManager {
         }
     }
 
-    /// Whether DASH streams are enabled (MPV only).
-    /// Disabled by default as DASH can be unreliable with some Invidious instances.
-    var dashEnabled: Bool {
-        get {
-            if let cached = _dashEnabled { return cached }
-            return bool(for: .dashEnabled, default: false)
-        }
-        set {
-            _dashEnabled = newValue
-            set(newValue, for: .dashEnabled)
-        }
-    }
-
     var allowSoftwareDecodedFormats: Bool {
         get {
             if let cached = _allowSoftwareDecodedFormats { return cached }

Yattee/Core/SettingsManager.swift

@@ -34,7 +34,6 @@ final class SettingsManager {
     var _preferredQuality: VideoQuality?
     var _cellularQuality: VideoQuality?
     var _backgroundPlaybackEnabled: Bool?
-    var _dashEnabled: Bool?
     var _preferredAudioLanguage: String?
     var _preferredSubtitlesLanguage: String?
     var _playerVolume: Float?
@@ -415,7 +414,6 @@ final class SettingsManager {
         _preferredQuality = nil
         _cellularQuality = nil
         _backgroundPlaybackEnabled = nil
-        _dashEnabled = nil
         _preferredAudioLanguage = nil
         _preferredSubtitlesLanguage = nil
         _playerVolume = nil

Yattee/Localizable.xcstrings

@@ -12181,16 +12181,6 @@
         }
       }
     },
-    "settings.playback.dash" : {
-      "localizations" : {
-        "en" : {
-          "stringUnit" : {
-            "state" : "translated",
-            "value" : "Enable DASH"
-          }
-        }
-      }
-    },
     "settings.playback.macOS.autoResizePlayer" : {
       "comment" : "Toggle for automatically resizing player window to match video aspect ratio",
       "localizations" : {

Yattee/Services/Player/BackendSwitcher.swift

@@ -306,16 +306,13 @@ final class BackendSwitcher {
             filteredMuxed = muxedStreams
         }
 
-        // Sort: prefer non-HLS/DASH (progressive) formats, then by resolution
+        // Sort: prefer progressive formats, then HLS, and only fall back to DASH as a last
+        // resort (DASH should never be chosen when any other format is available).
         let sortedMuxed = filteredMuxed.sorted { s1, s2 in
-            let format1 = StreamFormat.detect(from: s1)
+            let rank1 = muxedFormatRank(StreamFormat.detect(from: s1))
-            let format2 = StreamFormat.detect(from: s2)
+            let rank2 = muxedFormatRank(StreamFormat.detect(from: s2))
-            let isAdaptive1 = format1 == .hls || format1 == .dash
+            if rank1 != rank2 {
-            let isAdaptive2 = format2 == .hls || format2 == .dash
+                return rank1 < rank2
-
-            // Prefer progressive formats for non-live content
-            if isAdaptive1 != isAdaptive2 {
-                return !isAdaptive1 // non-adaptive (false) comes first
             }
             return (s1.resolution ?? .p360) > (s2.resolution ?? .p360)
         }
@@ -332,6 +329,17 @@ final class BackendSwitcher {
         return nil
     }
 
+    /// Ranks muxed formats for fallback selection (lower = preferred).
+    /// Progressive formats win, then HLS; DASH is the last resort and is only
+    /// selected when it is the only format available.
+    private func muxedFormatRank(_ format: StreamFormat) -> Int {
+        switch format {
+        case .dash: return 2
+        case .hls: return 1
+        default: return 0 // progressive
+        }
+    }
+
     /// Returns codec priority for video streams (higher = better for MPV).
     /// AV1 > VP9 > H.264/AVC
     private func videoCodecPriority(_ codec: String?) -> Int {

Yattee/Services/Player/PlayerService.swift

@@ -1901,7 +1901,6 @@ final class PlayerService {
 
     private func selectStreams(for backendType: PlayerBackendType, from streams: [Stream]) -> (video: Stream, audio: Stream?)? {
         let supportedFormats = backendType.supportedFormats
-        let dashEnabled = settingsManager?.dashEnabled ?? false
 
         // Get user's original quality preference (before network adjustments)
         let userPreferredQuality = settingsManager?.preferredQuality ?? .auto
@@ -1932,7 +1931,6 @@ final class PlayerService {
         let muxedStreams = streams.filter { stream in
             let format = StreamFormat.detect(from: stream)
             guard supportedFormats.contains(format) else { return false }
-            if format == .dash && !dashEnabled { return false }
             // Only include HLS/DASH if they have video (audio-only HLS/DASH should be treated as audio streams)
             if format == .hls || format == .dash {
                 return !stream.isAudioOnly
@@ -1972,7 +1970,7 @@ final class PlayerService {
                 LoggingService.shared.debug("Stream selection: Using HLS for live stream", category: .player)
                 return (hlsStream, nil)
             }
-            if dashEnabled, let dashStream = muxedStreams.first(where: { StreamFormat.detect(from: $0) == .dash }) {
+            if let dashStream = muxedStreams.first(where: { StreamFormat.detect(from: $0) == .dash }) {
                 LoggingService.shared.debug("Stream selection: Using DASH for live stream", category: .player)
                 return (dashStream, nil)
             }
@@ -2065,16 +2063,13 @@ final class PlayerService {
             filteredMuxed = muxedStreams
         }
 
-        // Sort: prefer non-HLS/DASH (progressive) formats, then by resolution
+        // Sort: prefer progressive formats, then HLS, and only fall back to DASH as a last
+        // resort (DASH should never be chosen when any other format is available).
         let sortedMuxed = filteredMuxed.sorted { s1, s2 in
-            let format1 = StreamFormat.detect(from: s1)
+            let rank1 = muxedFormatRank(StreamFormat.detect(from: s1))
-            let format2 = StreamFormat.detect(from: s2)
+            let rank2 = muxedFormatRank(StreamFormat.detect(from: s2))
-            let isAdaptive1 = format1 == .hls || format1 == .dash
+            if rank1 != rank2 {
-            let isAdaptive2 = format2 == .hls || format2 == .dash
+                return rank1 < rank2
-
-            // Prefer progressive formats for non-live content
-            if isAdaptive1 != isAdaptive2 {
-                return !isAdaptive1 // non-adaptive (false) comes first
             }
             return (s1.resolution ?? .p360) > (s2.resolution ?? .p360)
         }
@@ -2091,6 +2086,17 @@ final class PlayerService {
         return nil
     }
 
+    /// Ranks muxed formats for fallback selection (lower = preferred).
+    /// Progressive formats win, then HLS; DASH is the last resort and is only
+    /// selected when it is the only format available.
+    private func muxedFormatRank(_ format: StreamFormat) -> Int {
+        switch format {
+        case .dash: return 2
+        case .hls: return 1
+        default: return 0 // progressive
+        }
+    }
+
     /// Returns codec priority for video streams (higher = better).
     /// Prefers hardware-decodable codecs for battery efficiency.
     private func videoCodecPriority(_ codec: String?) -> Int {

Yattee/Views/Player/ExpandedPlayerSheet.swift

@@ -667,12 +667,11 @@ private struct PlayerSheetsModifier: ViewModifier {
     private var qualitySelectorSheet: some View {
         if let playerService {
             let supportedFormats = playerService.currentBackendType.supportedFormats
-            let dashEnabled = appEnvironment?.settingsManager.dashEnabled ?? false
             QualitySelectorView(
                 streams: playerService.availableStreams.filter { stream in
                     let format = StreamFormat.detect(from: stream)
-                    // Filter out DASH streams if disabled in settings
+                    // DASH is never offered for manual selection
-                    if format == .dash && !dashEnabled {
+                    if format == .dash {
                         return false
                     }
                     return supportedFormats.contains(format)

Yattee/Views/Player/tvOS/TVPlayerView.swift

@@ -143,13 +143,13 @@ struct TVPlayerView: View {
     @ViewBuilder
     private var qualityPanelContent: some View {
         if let playerService {
-            let dashEnabled = appEnvironment?.settingsManager.dashEnabled ?? false
             let supportedFormats = playerService.currentBackendType.supportedFormats
 
             QualitySelectorView(
                 streams: playerService.availableStreams.filter { stream in
                     let format = StreamFormat.detect(from: stream)
-                    if format == .dash && !dashEnabled {
+                    // DASH is never offered for manual selection
+                    if format == .dash {
                         return false
                     }
                     return supportedFormats.contains(format)

Yattee/Views/Settings/AdvancedSettingsView.swift

@@ -206,13 +206,6 @@ struct AdvancedSettingsView: View {
                     Label(String(localized: "settings.advanced.mpv.edl"), systemImage: "arrow.trianglehead.merge")
                 }
 
-                Toggle(isOn: Binding(
-                    get: { settingsManager.dashEnabled },
-                    set: { settingsManager.dashEnabled = $0 }
-                )) {
-                    Label(String(localized: "settings.playback.dash"), systemImage: "bolt.horizontal")
-                }
-
                 #if os(tvOS)
                 NavigationLink {
                     TVSidebarDetailContainer(