diff --git a/packager/app/test/testdata/ec3-packed-audio-encrypted/output.m3u8 b/packager/app/test/testdata/ec3-packed-audio-encrypted/output.m3u8
index 769aee0efb..7f8827fffb 100644
--- a/packager/app/test/testdata/ec3-packed-audio-encrypted/output.m3u8
+++ b/packager/app/test/testdata/ec3-packed-audio-encrypted/output.m3u8
@@ -5,7 +5,7 @@
 
 #EXT-X-MEDIA:TYPE=AUDIO,URI="bear-640x360-ec3-audio.m3u8",GROUP-ID="default-audio-group",NAME="stream_0",AUTOSELECT=YES,CHANNELS="2"
 
-#EXT-X-STREAM-INF:BANDWIDTH=1216655,AVERAGE-BANDWIDTH=1104925,CODECS="avc1.64001e,ec-3",RESOLUTION=640x360,FRAME-RATE=9.990,AUDIO="default-audio-group"
+#EXT-X-STREAM-INF:BANDWIDTH=1216655,AVERAGE-BANDWIDTH=1104925,CODECS="avc1.64001e,ec-3",RESOLUTION=640x360,FRAME-RATE=29.970,AUDIO="default-audio-group"
 bear-640x360-ec3-video.m3u8
 
 #EXT-X-I-FRAME-STREAM-INF:BANDWIDTH=217180,AVERAGE-BANDWIDTH=157213,CODECS="avc1.64001e",RESOLUTION=640x360,URI="bear-640x360-ec3-video-iframe.m3u8"
diff --git a/packager/media/formats/mp2t/ts_muxer.cc b/packager/media/formats/mp2t/ts_muxer.cc
index 4c5bab7e78..e3d6447ad4 100644
--- a/packager/media/formats/mp2t/ts_muxer.cc
+++ b/packager/media/formats/mp2t/ts_muxer.cc
@@ -34,10 +34,12 @@ Status TsMuxer::Finalize() {
 
 Status TsMuxer::AddSample(size_t stream_id, const MediaSample& sample) {
   DCHECK_EQ(stream_id, 0u);
-  if (sample_duration_ == 0) {
-    sample_duration_ = sample.duration() * kTsTimescale / streams().front()->time_scale();
-    if (muxer_listener()) 
-      muxer_listener()->OnSampleDurationReady(sample_duration_);
+  if (num_samples_ < 2) {
+    sample_durations_[num_samples_] = sample.duration() * kTsTimescale / 
+                                      streams().front()->time_scale();
+    if (num_samples_ == 1 && muxer_listener()) 
+      muxer_listener()->OnSampleDurationReady(sample_durations_[num_samples_]);
+    num_samples_++;
   } 
   return segmenter_->AddSample(sample);
 }
diff --git a/packager/media/formats/mp2t/ts_muxer.h b/packager/media/formats/mp2t/ts_muxer.h
index c2aab357cd..c4c0c4bc74 100644
--- a/packager/media/formats/mp2t/ts_muxer.h
+++ b/packager/media/formats/mp2t/ts_muxer.h
@@ -35,7 +35,8 @@ class TsMuxer : public Muxer {
   void FireOnMediaEndEvent();
 
   std::unique_ptr<TsSegmenter> segmenter_;
-  int64_t sample_duration_ = 0;
+  int64_t sample_durations_[2];
+  int64_t num_samples_ = 0;
 
   DISALLOW_COPY_AND_ASSIGN(TsMuxer);
 };