diff --git a/include/packager/packager.h b/include/packager/packager.h
index 6c7ad7a260..96fd0b0720 100644
--- a/include/packager/packager.h
+++ b/include/packager/packager.h
@@ -46,6 +46,10 @@ struct PackagingParams {
   /// audio) timestamps to compensate for possible negative timestamps in the
   /// input.
   int32_t transport_stream_timestamp_offset_ms = 0;
+  // the threshold used to determine if we should assume that the text stream
+  // actually starts at time zero
+  int32_t default_text_zero_bias_ms = 0;
+
   /// Chunking (segmentation) related parameters.
   ChunkingParams chunking_params;
 
diff --git a/packager/app/muxer_flags.cc b/packager/app/muxer_flags.cc
index bbee0ccf04..2a68b1ee91 100644
--- a/packager/app/muxer_flags.cc
+++ b/packager/app/muxer_flags.cc
@@ -62,3 +62,14 @@ ABSL_FLAG(int32_t,
           "input. For example, timestamps from ISO-BMFF after adjusted by "
           "EditList could be negative. In transport streams, timestamps are "
           "not allowed to be less than zero.");
+ABSL_FLAG(
+    int32_t,
+    default_text_zero_bias_ms,
+    0,
+    "A positive value, in milliseconds. It is the threshold used to "
+    "determine if we should assume that the text stream actually starts "
+    "at time zero. If the first sample comes before default_text_zero_bias_ms, "
+    "then the start will be padded as the stream is assumed to start at zero. "
+    "If the first sample comes after default_text_zero_bias_ms then the start "
+    "of the stream will not be padded as we cannot assume the start time of "
+    "the stream.");
diff --git a/packager/app/muxer_flags.h b/packager/app/muxer_flags.h
index 20ee2f72b7..a27aff8638 100644
--- a/packager/app/muxer_flags.h
+++ b/packager/app/muxer_flags.h
@@ -21,5 +21,6 @@ ABSL_DECLARE_FLAG(bool, generate_sidx_in_media_segments);
 ABSL_DECLARE_FLAG(std::string, temp_dir);
 ABSL_DECLARE_FLAG(bool, mp4_include_pssh_in_stream);
 ABSL_DECLARE_FLAG(int32_t, transport_stream_timestamp_offset_ms);
+ABSL_DECLARE_FLAG(int32_t, default_text_zero_bias_ms);
 
 #endif  // APP_MUXER_FLAGS_H_
diff --git a/packager/app/packager_main.cc b/packager/app/packager_main.cc
index 7651a0cd01..9e12798d60 100644
--- a/packager/app/packager_main.cc
+++ b/packager/app/packager_main.cc
@@ -461,6 +461,8 @@ std::optional<PackagingParams> GetPackagingParams() {
 
   packaging_params.transport_stream_timestamp_offset_ms =
       absl::GetFlag(FLAGS_transport_stream_timestamp_offset_ms);
+  packaging_params.default_text_zero_bias_ms =
+      absl::GetFlag(FLAGS_default_text_zero_bias_ms);
 
   packaging_params.output_media_info = absl::GetFlag(FLAGS_output_media_info);
 
diff --git a/packager/media/formats/webvtt/text_padder.cc b/packager/media/formats/webvtt/text_padder.cc
index 8bb9cf4c6c..f93b60200b 100644
--- a/packager/media/formats/webvtt/text_padder.cc
+++ b/packager/media/formats/webvtt/text_padder.cc
@@ -40,7 +40,9 @@ Status TextPadder::OnTextSample(std::unique_ptr<StreamData> data) {
   // start at time zero.
   if (max_end_time_ms_ < 0) {
     max_end_time_ms_ =
-        sample.start_time() > zero_start_bias_ms_ ? sample.start_time() : 0;
+        zero_start_bias_ms_ && sample.start_time() > zero_start_bias_ms_
+            ? sample.start_time()
+            : 0;
   }
 
   // Check if there will be a gap between samples if we just dispatch this
diff --git a/packager/packager.cc b/packager/packager.cc
index 8f0196322d..05993f978d 100644
--- a/packager/packager.cc
+++ b/packager/packager.cc
@@ -59,8 +59,6 @@ namespace {
 
 const char kMediaInfoSuffix[] = ".media_info";
 
-const int64_t kDefaultTextZeroBiasMs = 10 * 60 * 1000;  // 10 minutes
-
 MuxerListenerFactory::StreamData ToMuxerListenerData(
     const StreamDescriptor& stream) {
   MuxerListenerFactory::StreamData data;
@@ -662,8 +660,8 @@ Status CreateAudioVideoJobs(
 
       std::vector<std::shared_ptr<MediaHandler>> handlers;
       if (is_text) {
-        handlers.emplace_back(
-            std::make_shared<TextPadder>(kDefaultTextZeroBiasMs));
+        handlers.emplace_back(std::make_shared<TextPadder>(
+            packaging_params.default_text_zero_bias_ms));
       }
       if (sync_points) {
         handlers.emplace_back(cue_aligner);