diff --git a/mkvmuxer.cpp b/mkvmuxer.cpp
index e81545d..b1bb689 100644
--- a/mkvmuxer.cpp
+++ b/mkvmuxer.cpp
@@ -514,6 +514,8 @@ Track::Track(unsigned int* seed)
       number_(0),
       type_(0),
       uid_(MakeUID(seed)),
+      codec_delay_(0),
+      seek_pre_roll_(0),
       codec_private_length_(0),
       content_encoding_entries_(NULL),
       content_encoding_entries_size_(0) {
@@ -635,6 +637,11 @@ bool Track::Write(IMkvWriter* writer) const {
     size += EbmlElementSize(kMkvName, name_);
   if (max_block_additional_id_)
     size += EbmlElementSize(kMkvMaxBlockAdditionID, max_block_additional_id_);
+  if (codec_delay_)
+    size += EbmlElementSize(kMkvCodecDelay, codec_delay_);
+  if (seek_pre_roll_)
+    size += EbmlElementSize(kMkvSeekPreRoll, seek_pre_roll_);
+
 
   const int64 payload_position = writer->Position();
   if (payload_position < 0)
@@ -646,11 +653,21 @@ bool Track::Write(IMkvWriter* writer) const {
     return false;
   if (!WriteEbmlElement(writer, kMkvTrackType, type_))
     return false;
-  if (max_block_additional_id_)
+  if (max_block_additional_id_) {
     if (!WriteEbmlElement(writer,
                           kMkvMaxBlockAdditionID,
-                          max_block_additional_id_))
+                          max_block_additional_id_)) {
       return false;
+    }
+  }
+  if (codec_delay_) {
+    if (!WriteEbmlElement(writer, kMkvCodecDelay, codec_delay_))
+      return false;
+  }
+  if (seek_pre_roll_) {
+    if (!WriteEbmlElement(writer, kMkvSeekPreRoll, seek_pre_roll_))
+      return false;
+  }
   if (codec_id_) {
     if (!WriteEbmlElement(writer, kMkvCodecID, codec_id_))
       return false;
diff --git a/mkvmuxer.hpp b/mkvmuxer.hpp
index 9f88432..db0a053 100644
--- a/mkvmuxer.hpp
+++ b/mkvmuxer.hpp
@@ -340,6 +340,12 @@ class Track {
   uint64 type() const { return type_; }
   void set_uid(uint64 uid) { uid_ = uid; }
   uint64 uid() const { return uid_; }
+  void set_codec_delay(uint64 codec_delay) { codec_delay_ = codec_delay; }
+  uint64 codec_delay() const { return codec_delay_; }
+  void set_seek_pre_roll(uint64 seek_pre_roll) {
+    seek_pre_roll_ = seek_pre_roll;
+  }
+  uint64 seek_pre_roll() const { return seek_pre_roll_; }
 
   uint64 codec_private_length() const { return codec_private_length_; }
   uint32 content_encoding_entries_size() const {
@@ -356,6 +362,8 @@ class Track {
   uint64 number_;
   uint64 type_;
   uint64 uid_;
+  uint64 codec_delay_;
+  uint64 seek_pre_roll_;
 
   // Size of the CodecPrivate data in bytes.
   uint64 codec_private_length_;
diff --git a/sample_muxer.cpp b/sample_muxer.cpp
index 8896389..1440c86 100644
--- a/sample_muxer.cpp
+++ b/sample_muxer.cpp
@@ -398,6 +398,11 @@ int main(int argc, char* argv[]) {
       const long long bit_depth = pAudioTrack->GetBitDepth();
       if (bit_depth > 0)
         audio->set_bit_depth(bit_depth);
+
+      if (pAudioTrack->GetCodecDelay())
+        audio->set_codec_delay(pAudioTrack->GetCodecDelay());
+      if (pAudioTrack->GetSeekPreRoll())
+        audio->set_seek_pre_roll(pAudioTrack->GetSeekPreRoll());
     }
   }
 
diff --git a/webmids.hpp b/webmids.hpp
index fe02926..3930cd0 100644
--- a/webmids.hpp
+++ b/webmids.hpp
@@ -74,6 +74,8 @@ enum MkvId {
   kMkvCodecPrivate            = 0x63A2,
   kMkvCodecName               = 0x258688,
   kMkvMaxBlockAdditionID      = 0x55EE,
+  kMkvCodecDelay              = 0x56AA,
+  kMkvSeekPreRoll             = 0x56BB,
   //video
   kMkvVideo                   = 0xE0,
   kMkvFlagInterlaced          = 0x9A,