Always apply timestamp normalization

- Remove CopyTimestamps condition check
- Apply -avoid_negative_ts make_zero -start_at_zero to all transcodes
- Fixes MKV files with negative audio timestamps
- Client copyTimestamps parameter was preventing the fix

MediaBrowser.Controller/MediaEncoding/EncodingHelper.cs

@@ -7504,12 +7504,9 @@ namespace MediaBrowser.Controller.MediaEncoding
             var inputModifier = GetInputModifier(state, encodingOptions, null);
 
             // Add timestamp normalization to fix seeking issues
-            // Fixes seeking issues in strict players like mpv, iina, and infuse
-            var timestampArgs = string.Empty;
-            if (!state.BaseRequest.CopyTimestamps)
-            {
-                timestampArgs = " -avoid_negative_ts make_zero -start_at_zero";
-            }
+            // Always normalize timestamps - fixes seeking issues in strict players like mpv, iina, and infuse
+            // This prevents negative timestamps in output, regardless of input
+            var timestampArgs = " -avoid_negative_ts make_zero -start_at_zero";
 
             return string.Format(
                 CultureInfo.InvariantCulture,