diff --git a/app/codec/decoder.cpp b/app/codec/decoder.cpp
index 9da151b7c..0eebf8055 100644
--- a/app/codec/decoder.cpp
+++ b/app/codec/decoder.cpp
@@ -335,7 +335,7 @@ void Decoder::UpdateLastAccessed()
 
 uint qHash(Decoder::CodecStream stream, uint seed)
 {
-  return qHash(stream.filename(), seed) ^ qHash(stream.stream(), seed);
+  return qHash(stream.filename(), seed) ^ qHash(stream.stream(), seed) ^ qHash(stream.block(), seed);
 }
 
 }
diff --git a/app/node/traverser.cpp b/app/node/traverser.cpp
index a75ab921e..ed7aae25d 100644
--- a/app/node/traverser.cpp
+++ b/app/node/traverser.cpp
@@ -350,7 +350,9 @@ NodeValueTable NodeTraverser::GenerateBlockTable(const Track *track, const TimeR
   NodeValueTable table;
 
   if (active_block) {
+    block_stack_.push_back(active_block);
     table = GenerateTable(active_block, Track::TransformRangeForBlock(active_block, range), track);
+    block_stack_.pop_back();
   }
 
   return table;
diff --git a/app/node/traverser.h b/app/node/traverser.h
index e129096ab..524fc8337 100644
--- a/app/node/traverser.h
+++ b/app/node/traverser.h
@@ -151,6 +151,11 @@ protected:
 
   void ResolveJobs(NodeValue &value, const TimeRange &range);
 
+  Block *GetCurrentBlock() const
+  {
+    return block_stack_.empty() ? nullptr : block_stack_.back();
+  }
+
 private:
   void PreProcessRow(const TimeRange &range, NodeValueRow &row);
 
@@ -167,6 +172,8 @@ private:
   const Node *transform_now_;
   QTransform *transform_;
 
+  std::list<Block*> block_stack_;
+
 };
 
 }
diff --git a/app/render/renderprocessor.cpp b/app/render/renderprocessor.cpp
index 31fc78ec6..22715de65 100644
--- a/app/render/renderprocessor.cpp
+++ b/app/render/renderprocessor.cpp
@@ -255,10 +255,10 @@ DecoderPtr RenderProcessor::ResolveDecoderFromInput(const QString& decoder_id, c
     // No decoder
     decoder.decoder = Decoder::CreateFromID(decoder_id);
     decoder.last_modified = file_last_modified;
+    decoder_cache_->insert(stream, decoder);
+    locker.unlock();
 
-    if (decoder.decoder->Open(stream)) {
-      decoder_cache_->insert(stream, decoder);
-    } else {
+    if (!decoder.decoder->Open(stream)) {
       qWarning() << "Failed to open decoder for" << stream.filename()
                  << "::" << stream.stream();
       return nullptr;
@@ -421,7 +421,7 @@ void RenderProcessor::ProcessVideoFootage(TexturePtr destination, const FootageJ
     qWarning() << "HAVEN'T GOTTEN DEFAULT INPUT COLORSPACE";
   }
 
-  Decoder::CodecStream default_codec_stream(stream.filename(), stream_data.stream_index());
+  Decoder::CodecStream default_codec_stream(stream.filename(), stream_data.stream_index(), GetCurrentBlock());
 
   QString decoder_id = stream.decoder();
 
@@ -443,7 +443,7 @@ void RenderProcessor::ProcessVideoFootage(TexturePtr destination, const FootageJ
     frame_filename = Decoder::TransformImageSequenceFileName(stream.filename(), frame_number);
 
     // Decoder will close automatically since it's a stream_ptr
-    decoder->Open(Decoder::CodecStream(frame_filename, stream_data.stream_index()));
+    decoder->Open(Decoder::CodecStream(frame_filename, stream_data.stream_index(), GetCurrentBlock()));
     break;
   }
   }
@@ -489,7 +489,7 @@ void RenderProcessor::ProcessVideoFootage(TexturePtr destination, const FootageJ
 
 void RenderProcessor::ProcessAudioFootage(SampleBuffer &destination, const FootageJob &stream, const TimeRange &input_time)
 {
-  DecoderPtr decoder = ResolveDecoderFromInput(stream.decoder(), Decoder::CodecStream(stream.filename(), stream.audio_params().stream_index()));
+  DecoderPtr decoder = ResolveDecoderFromInput(stream.decoder(), Decoder::CodecStream(stream.filename(), stream.audio_params().stream_index(), nullptr));
 
   if (decoder) {
     const AudioParams& audio_params = GetCacheAudioParams();