diff --git a/go_backend/exports.go b/go_backend/exports.go
index 4537e49e..1c353cc8 100644
--- a/go_backend/exports.go
+++ b/go_backend/exports.go
@@ -313,6 +313,7 @@ type DownloadResponse struct {
 	AlreadyExists               bool                    `json:"already_exists,omitempty"`
 	ActualBitDepth              int                     `json:"actual_bit_depth,omitempty"`
 	ActualSampleRate            int                     `json:"actual_sample_rate,omitempty"`
+	AudioCodec                  string                  `json:"audio_codec,omitempty"`
 	ActualExtension             string                  `json:"actual_extension,omitempty"`
 	ActualContainer             string                  `json:"actual_container,omitempty"`
 	RequiresContainerConversion bool                    `json:"requires_container_conversion,omitempty"`
@@ -342,6 +343,7 @@ type DownloadResult struct {
 	FilePath                    string
 	BitDepth                    int
 	SampleRate                  int
+	AudioCodec                  string
 	Title                       string
 	Artist                      string
 	Album                       string
@@ -863,6 +865,7 @@ func buildDownloadSuccessResponse(
 		AlreadyExists:               alreadyExists,
 		ActualBitDepth:              result.BitDepth,
 		ActualSampleRate:            result.SampleRate,
+		AudioCodec:                  result.AudioCodec,
 		ActualExtension:             result.ActualExtension,
 		ActualContainer:             result.ActualContainer,
 		RequiresContainerConversion: result.RequiresContainerConversion,
@@ -920,7 +923,12 @@ func enrichResultQualityFromFile(result *DownloadResult) {
 	if qErr == nil {
 		result.BitDepth = quality.BitDepth
 		result.SampleRate = quality.SampleRate
-		GoLog("[Download] Actual quality from file: %d-bit/%dHz\n", quality.BitDepth, quality.SampleRate)
+		result.AudioCodec = quality.Codec
+		if quality.Codec != "" {
+			GoLog("[Download] Actual quality from file: %s %d-bit/%dHz\n", quality.Codec, quality.BitDepth, quality.SampleRate)
+		} else {
+			GoLog("[Download] Actual quality from file: %d-bit/%dHz\n", quality.BitDepth, quality.SampleRate)
+		}
 		return
 	}
 
diff --git a/go_backend/extension_providers.go b/go_backend/extension_providers.go
index 33f5f539..60531362 100644
--- a/go_backend/extension_providers.go
+++ b/go_backend/extension_providers.go
@@ -236,6 +236,7 @@ func normalizeExtensionDownloadResult(result *ExtDownloadResult) (DownloadResult
 		FilePath:                    strings.TrimSpace(result.FilePath),
 		BitDepth:                    result.BitDepth,
 		SampleRate:                  result.SampleRate,
+		AudioCodec:                  strings.TrimSpace(result.AudioCodec),
 		Title:                       result.Title,
 		Artist:                      result.Artist,
 		Album:                       result.Album,
@@ -420,6 +421,7 @@ type ExtDownloadResult struct {
 	AlreadyExists bool   `json:"already_exists,omitempty"`
 	BitDepth      int    `json:"bit_depth,omitempty"`
 	SampleRate    int    `json:"sample_rate,omitempty"`
+	AudioCodec    string `json:"audio_codec,omitempty"`
 	ErrorMessage  string `json:"error_message,omitempty"`
 	ErrorType     string `json:"error_type,omitempty"`
 
@@ -873,6 +875,7 @@ func parseExtensionDownloadResultValue(vm *goja.Runtime, value goja.Value) ExtDo
 		AlreadyExists:   gojaObjectBool(obj, "already_exists", "alreadyExists"),
 		BitDepth:        gojaObjectInt(obj, "bit_depth", "bitDepth"),
 		SampleRate:      gojaObjectInt(obj, "sample_rate", "sampleRate"),
+		AudioCodec:      gojaObjectString(obj, "audio_codec", "audioCodec", "codec"),
 		ErrorMessage:    gojaObjectString(obj, "error_message", "errorMessage", "error"),
 		ErrorType:       gojaObjectString(obj, "error_type", "errorType"),
 		Title:           gojaObjectString(obj, "title"),
diff --git a/go_backend/extension_runtime_ffmpeg.go b/go_backend/extension_runtime_ffmpeg.go
index 8269e919..d9a9e2a5 100644
--- a/go_backend/extension_runtime_ffmpeg.go
+++ b/go_backend/extension_runtime_ffmpeg.go
@@ -131,6 +131,7 @@ func (r *extensionRuntime) ffmpegGetInfo(call goja.FunctionCall) goja.Value {
 		"sample_rate":   quality.SampleRate,
 		"total_samples": quality.TotalSamples,
 		"duration":      float64(quality.TotalSamples) / float64(quality.SampleRate),
+		"codec":         quality.Codec,
 	})
 }
 
diff --git a/go_backend/extension_runtime_file.go b/go_backend/extension_runtime_file.go
index 8ef83fdc..1634022b 100644
--- a/go_backend/extension_runtime_file.go
+++ b/go_backend/extension_runtime_file.go
@@ -136,6 +136,7 @@ func (r *extensionRuntime) fileDownload(call goja.FunctionCall) goja.Value {
 	var onProgress goja.Callable
 	var headers map[string]string
 	var chunkedDownload bool
+	trackItemBytes := true
 	var chunkSize int64
 	if len(call.Arguments) > 2 && !goja.IsUndefined(call.Arguments[2]) && !goja.IsNull(call.Arguments[2]) {
 		optionsObj := call.Arguments[2].Export()
@@ -151,6 +152,15 @@ func (r *extensionRuntime) fileDownload(call goja.FunctionCall) goja.Value {
 					onProgress = callable
 				}
 			}
+			if trackBytes, ok := opts["trackItemBytes"]; ok {
+				if v, ok := trackBytes.(bool); ok {
+					trackItemBytes = v
+				}
+			} else if trackBytes, ok := opts["track_item_bytes"]; ok {
+				if v, ok := trackBytes.(bool); ok {
+					trackItemBytes = v
+				}
+			}
 			if chunked, ok := opts["chunked"]; ok {
 				switch v := chunked.(type) {
 				case bool:
@@ -194,7 +204,7 @@ func (r *extensionRuntime) fileDownload(call goja.FunctionCall) goja.Value {
 	}
 
 	if chunkedDownload {
-		return r.fileDownloadChunked(client, urlStr, fullPath, headers, ua, chunkSize, onProgress)
+		return r.fileDownloadChunked(client, urlStr, fullPath, headers, ua, chunkSize, onProgress, trackItemBytes)
 	}
 
 	req, err := http.NewRequest("GET", urlStr, nil)
@@ -244,7 +254,7 @@ func (r *extensionRuntime) fileDownload(call goja.FunctionCall) goja.Value {
 	}
 
 	contentLength := resp.ContentLength
-	shouldTrackItemBytes := activeItemID != ""
+	shouldTrackItemBytes := activeItemID != "" && trackItemBytes
 	if shouldTrackItemBytes && contentLength > 0 {
 		SetItemBytesTotal(activeItemID, contentLength)
 	}
@@ -321,7 +331,7 @@ func (r *extensionRuntime) fileDownload(call goja.FunctionCall) goja.Value {
 // fileDownloadChunked downloads a URL using sequential Range requests.
 // This is needed for servers (like YouTube's googlevideo CDN) that reject
 // non-ranged or large-range requests with 403 and require small chunk downloads.
-func (r *extensionRuntime) fileDownloadChunked(client *http.Client, urlStr, fullPath string, headers map[string]string, ua string, chunkSize int64, onProgress goja.Callable) goja.Value {
+func (r *extensionRuntime) fileDownloadChunked(client *http.Client, urlStr, fullPath string, headers map[string]string, ua string, chunkSize int64, onProgress goja.Callable, trackItemBytes bool) goja.Value {
 	// First, get the total content length with a small probe request
 	probeReq, err := http.NewRequest("GET", urlStr, nil)
 	if err != nil {
@@ -391,7 +401,7 @@ func (r *extensionRuntime) fileDownloadChunked(client *http.Client, urlStr, full
 		SetItemDownloading(activeItemID)
 	}
 
-	shouldTrackItemBytes := activeItemID != ""
+	shouldTrackItemBytes := activeItemID != "" && trackItemBytes
 	if shouldTrackItemBytes && totalSize > 0 {
 		SetItemBytesTotal(activeItemID, totalSize)
 	}
diff --git a/go_backend/extension_runtime_utils.go b/go_backend/extension_runtime_utils.go
index e06541e6..8b568c9b 100644
--- a/go_backend/extension_runtime_utils.go
+++ b/go_backend/extension_runtime_utils.go
@@ -415,6 +415,7 @@ func (r *extensionRuntime) RegisterGoBackendAPIs(vm *goja.Runtime) {
 			"sampleRate":   quality.SampleRate,
 			"totalSamples": quality.TotalSamples,
 			"duration":     quality.Duration,
+			"codec":        quality.Codec,
 		})
 	})
 
diff --git a/lib/providers/download_queue_provider.dart b/lib/providers/download_queue_provider.dart
index 8f066b9d..13c7637d 100644
--- a/lib/providers/download_queue_provider.dart
+++ b/lib/providers/download_queue_provider.dart
@@ -6246,6 +6246,16 @@ class DownloadQueueNotifier extends Notifier<DownloadQueueState> {
     if (context.quality == 'HIGH' || context.outputExt != '.flac') {
       return filePath;
     }
+    final resultAudioFormat = _normalizeAudioFormatValue(
+      result['audio_codec']?.toString() ??
+          result['actual_audio_codec']?.toString(),
+    );
+    if (_isLossyAudioFormat(resultAudioFormat)) {
+      _log.d(
+        'Native-worker output is $resultAudioFormat; preserving native container.',
+      );
+      return filePath;
+    }
     final requiresContainerConversion =
         result['requires_container_conversion'] == true ||
         result['requiresContainerConversion'] == true;
@@ -7411,10 +7421,16 @@ class DownloadQueueNotifier extends Notifier<DownloadQueueState> {
           result,
           filePath: filePath,
         );
+        final resultAudioFormat = _normalizeAudioFormatValue(
+          result['audio_codec']?.toString() ??
+              result['actual_audio_codec']?.toString(),
+        );
+        final resultIsLossyAudio = _isLossyAudioFormat(resultAudioFormat);
         final requiresContainerConversion =
             result['requires_container_conversion'] == true ||
             result['requiresContainerConversion'] == true ||
-            _shouldRequestContainerConversion(actualService, safOutputExt);
+            (!resultIsLossyAudio &&
+                _shouldRequestContainerConversion(actualService, safOutputExt));
         final preferredOutputExt = _extensionPreferredOutputExt(actualService);
         final shouldPreserveNativeM4a =
             !requiresContainerConversion &&