200ms webm daily doc

server/docs/video-platforms/README.md

@@ -176,15 +176,17 @@ Parse timestamps:
 Track 0:
   Filename offset: 438ms
   PyAV metadata:   229ms
-  Difference:      209ms
+  Difference:      ~200ms
 
 Track 1:
   Filename offset: 8339ms
   PyAV metadata:   8130ms
-  Difference:      209ms
+  Difference:      ~200ms
 ```
 
-**Consistent 209ms delta** suggests network/encoding delay between file upload initiation (filename) and actual audio stream start (metadata).
+**Consistent ~200ms delta** suggests network/encoding delay between file upload initiation (filename) and actual audio stream start (metadata).
+
+**Note:** The ~200ms difference observed in this test recording is not crucial for timing accuracy. Either method (filename timestamps or PyAV metadata) works well for multi-track alignment. Filename timestamps are preferable as they are better officially documented by Daily.co.
 
 **Current implementation uses PyAV metadata** because:
 - More accurate (represents when audio actually started)

server/reflector/pipelines/main_multitrack_pipeline.py

@@ -91,12 +91,12 @@ class PipelineMainMultitrack(PipelineMainBase):
             - Track 0: (1760988935922 - 1760988935484) / 1000 = 0.438s
             - Track 1: (1760988943823 - 1760988935484) / 1000 = 8.339s
 
-            TIME DIFFERENCE: PyAV metadata vs filename timestamps differ by ~209ms:
-            - Track 0: filename=438ms, metadata=229ms (diff: 209ms)
-            - Track 1: filename=8339ms, metadata=8130ms (diff: 209ms)
+            TIME DIFFERENCE: PyAV metadata vs filename timestamps differ by ~200ms:
+            - Track 0: filename=438ms, metadata=229ms (diff: ~200ms)
+            - Track 1: filename=8339ms, metadata=8130ms (diff: ~200ms)
 
-            Consistent delta suggests network/encoding delay. PyAV metadata is ground truth
-            (represents when audio stream actually started vs when file upload initiated).
+            Note: The ~200ms difference isn't crucial - either method works for alignment.
+            Filename timestamps are preferable due to being better officially documented.
 
             Example with 2 participants:
                 Track A: start_time=0.2s → Joined 200ms after recording began

server/reflector/utils/audio_padding.py

@@ -25,7 +25,9 @@ def extract_stream_start_time_from_container(
     """Extract meeting-relative start time from WebM stream metadata.
 
     Uses PyAV to read stream.start_time from WebM container.
-    More accurate than filename timestamps by ~209ms due to network/encoding delays.
+    Note: Differs from filename timestamps by ~200ms in test recordings, but this difference
+    is not crucial - either method works. Filename timestamps are preferable due to being
+    better officially documented by Daily.co.
 
     Args:
         container: PyAV container opened from audio file/URL