diff --git a/FFMpegCore/FFMPEG/Argument/Atoms/InputArgument.cs b/FFMpegCore/FFMPEG/Argument/Atoms/InputArgument.cs
index 9c6e084..a04f980 100644
--- a/FFMpegCore/FFMPEG/Argument/Atoms/InputArgument.cs
+++ b/FFMpegCore/FFMPEG/Argument/Atoms/InputArgument.cs
@@ -40,5 +40,9 @@ public override string GetStringValue()
         {
             return string.Join(" ", Value.Select(v => ArgumentStringifier.Input(v)));
         }
+        public VideoInfo[] GetAsVideoInfo()
+        {
+            return Value.Select(v => new VideoInfo(v)).ToArray();
+        }
     }
 }
diff --git a/FFMpegCore/FFMPEG/FFMpeg.cs b/FFMpegCore/FFMPEG/FFMpeg.cs
index bb83813..de44268 100644
--- a/FFMpegCore/FFMPEG/FFMpeg.cs
+++ b/FFMpegCore/FFMPEG/FFMpeg.cs
@@ -436,14 +436,21 @@ public VideoInfo ReplaceAudio(VideoInfo source, FileInfo audio, FileInfo output,
 
         public VideoInfo Convert(ArgumentContainer arguments)
         {
-            var args = ArgumentBuilder.BuildArguments(arguments);
             var output = ((OutputArgument)arguments[typeof(OutputArgument)]).GetAsFileInfo();
+            var sources = ((InputArgument)arguments[typeof(InputArgument)]).GetAsVideoInfo();
+
+            // Sum duration of all sources
+            _totalTime = TimeSpan.Zero;
+            foreach (var source in sources)
+                _totalTime += source.Duration;
 
             if (!RunProcess(arguments, output))
             {
                 throw new FFMpegException(FFMpegExceptionType.Operation, "Could not replace the video audio.");
             }
 
+            _totalTime = TimeSpan.MinValue;
+
             return new VideoInfo(output);
         }