diff --git a/Packages/com.github.homuler.mediapipe/Runtime/Scripts/Unity/GlobalInstanceTable.cs b/Packages/com.github.homuler.mediapipe/Runtime/Scripts/Unity/GlobalInstanceTable.cs
index 9f99219fa..1e62eec9d 100644
--- a/Packages/com.github.homuler.mediapipe/Runtime/Scripts/Unity/GlobalInstanceTable.cs
+++ b/Packages/com.github.homuler.mediapipe/Runtime/Scripts/Unity/GlobalInstanceTable.cs
@@ -81,7 +81,7 @@ private void ClearUnusedKeys()
     {
       lock (((ICollection)_table).SyncRoot)
       {
-        var deadKeys = _table.Where(x => !x.Value.TryGetTarget(out var target)).Select(x => x.Key);
+        var deadKeys = _table.Where(x => !x.Value.TryGetTarget(out var target)).Select(x => x.Key).ToArray();
 
         foreach (var key in deadKeys)
         {
diff --git a/Packages/com.github.homuler.mediapipe/Runtime/Scripts/Unity/OutputStream.cs b/Packages/com.github.homuler.mediapipe/Runtime/Scripts/Unity/OutputStream.cs
index 34e88382e..79a0bbbea 100644
--- a/Packages/com.github.homuler.mediapipe/Runtime/Scripts/Unity/OutputStream.cs
+++ b/Packages/com.github.homuler.mediapipe/Runtime/Scripts/Unity/OutputStream.cs
@@ -470,7 +470,7 @@ protected static void CompressCallbackStatus()
     {
       lock (((ICollection)_CallbackStatus).SyncRoot)
       {
-        var deadKeys = _CallbackStatus.Where(x => !_InstanceTable.ContainsKey(x.Key)).Select(x => x.Key);
+        var deadKeys = _CallbackStatus.Where(x => !_InstanceTable.ContainsKey(x.Key)).Select(x => x.Key).ToArray();
 
         foreach (var key in deadKeys)
         {