diff --git a/BasicNodes/BasicNodes.csproj b/BasicNodes/BasicNodes.csproj
index 805ad689..caca0dbe 100644
Binary files a/BasicNodes/BasicNodes.csproj and b/BasicNodes/BasicNodes.csproj differ
diff --git a/Builds/BasicNodes.zip b/Builds/BasicNodes.zip
index e1d83390..3666644a 100644
Binary files a/Builds/BasicNodes.zip and b/Builds/BasicNodes.zip differ
diff --git a/Builds/MetaNodes.zip b/Builds/MetaNodes.zip
index a1468aa3..e71ee5d3 100644
Binary files a/Builds/MetaNodes.zip and b/Builds/MetaNodes.zip differ
diff --git a/Builds/VideoNodes.zip b/Builds/VideoNodes.zip
index 581fe18d..b03ccd2c 100644
Binary files a/Builds/VideoNodes.zip and b/Builds/VideoNodes.zip differ
diff --git a/MetaNodes/MetaNodes.csproj b/MetaNodes/MetaNodes.csproj
index aae95b3a..2af5c0bc 100644
Binary files a/MetaNodes/MetaNodes.csproj and b/MetaNodes/MetaNodes.csproj differ
diff --git a/VideoNodes/ExtensionMethods.cs b/VideoNodes/ExtensionMethods.cs
index 01f63af9..e9c21ba7 100644
--- a/VideoNodes/ExtensionMethods.cs
+++ b/VideoNodes/ExtensionMethods.cs
@@ -1,10 +1,4 @@
-using System;
-using System.Collections.Generic;
-using System.Linq;
-using System.Text;
-using System.Threading.Tasks;
-
-namespace VideoNodes
+namespace FileFlows.VideoNodes
 {
     internal static class ExtensionMethods
     {
@@ -12,7 +6,11 @@ namespace VideoNodes
             if (dict.ContainsKey(key))
                 dict[key] = value;
             else
-                dict.Add(key, value);   
+                dict.Add(key, value);
+        }
+        public static string? EmptyAsNull(this string str)
+        {
+            return str == string.Empty ? null : str;
         }
     }
 }
diff --git a/VideoNodes/VideoNodes.csproj b/VideoNodes/VideoNodes.csproj
index 2c8d91fd..401201f5 100644
Binary files a/VideoNodes/VideoNodes.csproj and b/VideoNodes/VideoNodes.csproj differ
diff --git a/VideoNodes/VideoNodes/VideoEncode.cs b/VideoNodes/VideoNodes/VideoEncode.cs
index c5047ec5..74bc5273 100644
--- a/VideoNodes/VideoNodes/VideoEncode.cs
+++ b/VideoNodes/VideoNodes/VideoEncode.cs
@@ -51,7 +51,7 @@ namespace FileFlows.VideoNodes
             VideoCodecParameters = args.ReplaceVariables(VideoCodecParameters);
             AudioCodec = args.ReplaceVariables(AudioCodec);
             Language = args.ReplaceVariables(Language);
-            Extension = args.ReplaceVariables(Extension);
+            Extension = args.ReplaceVariables(Extension)?.EmptyAsNull() ?? "mkv";
 
             VideoCodec = VideoCodec.ToLower();
             AudioCodec = AudioCodec.ToLower();
@@ -92,6 +92,8 @@ namespace FileFlows.VideoNodes
                 bool audioRightCodec = bestAudio?.Codec?.ToLower() == AudioCodec && videoInfo.AudioStreams[0] == bestAudio;
                 args.Logger?.ILog("Best Audio: ", bestAudio == null ? "null" : (object)bestAudio);
 
+                bool sameContainer = new FileInfo(args.WorkingFile).Extension.ToLower() == Extension.ToLower();
+
 
                 string crop = args.GetParameter<string>(DetectBlackBars.CROP_KEY) ?? "";
                 if (crop != string.Empty)
@@ -123,7 +125,7 @@ namespace FileFlows.VideoNodes
 
                 TotalTime = videoInfo.VideoStreams[0].Duration;
 
-                if (audioRightCodec == false || videoIsRightCodec == null) // always redo audio if video is wrong codec, as this can lead to some failed encodes (found in mp4s to mkvs)
+                if (audioRightCodec == false || sameContainer == false) // if container changes, re-encode audio, otherwise this can lead to failed encodings (mp4 to mkv this can happen... a lot)
                     ffArgs.Add($"-map 0:{bestAudio!.Index} -c:a {AudioCodec}");
                 else
                     ffArgs.Add($"-map 0:{bestAudio!.Index} -c:a copy");
diff --git a/VideoNodes/VideoNodes/VideoNode.cs b/VideoNodes/VideoNodes/VideoNode.cs
index 66e2badf..74d9a0a8 100644
--- a/VideoNodes/VideoNodes/VideoNode.cs
+++ b/VideoNodes/VideoNodes/VideoNode.cs
@@ -1,7 +1,6 @@
 namespace FileFlows.VideoNodes
 {
     using FileFlows.Plugin;
-    using global::VideoNodes;
 
     public abstract class VideoNode : Node
     {
diff --git a/plugins.json b/plugins.json
index 249433a1..858cb8fc 100644
--- a/plugins.json
+++ b/plugins.json
@@ -1,17 +1,17 @@
 [
 	{
 		"Name": "BasicNodes",
-		"Version": "0.0.1.26",
+		"Version": "0.0.1.27",
 		"Package": "https://github.com/revenz/FileFlowsPlugins/blob/master/Builds/BasicNodes.zip?raw=true"
 	},
 	{
 		"Name": "MetaNodes",
-		"Version": "0.0.1.26",
+		"Version": "0.0.1.27",
 		"Package": "https://github.com/revenz/FileFlowsPlugins/blob/master/Builds/MetaNodes.zip?raw=true"
 	},
 	{
 		"Name": "VideoNodes",
-		"Version": "0.0.1.26",
+		"Version": "0.0.1.27",
 		"Package": "https://github.com/revenz/FileFlowsPlugins/blob/master/Builds/VideoNodes.zip?raw=true"
 	}
 ]