diff --git a/nginx-transcoder/nginx-no-ssl.conf b/nginx-transcoder/nginx-no-ssl.conf
index 13d2164..4941ca0 100644
--- a/nginx-transcoder/nginx-no-ssl.conf
+++ b/nginx-transcoder/nginx-no-ssl.conf
@@ -16,6 +16,13 @@ rtmp {
 
         application live {
             live on;
+            # Start the exec'd transcoder's input at a keyframe with audio held
+            # until video flows, so both tracks begin together. Without these,
+            # the subscriber gets audio up to one GOP before decodable video and
+            # ffmpeg records that skew as a leading empty edit on the video
+            # track, which desyncs players that drop edit lists in MSE.
+            wait_key on;
+            wait_video on;
             on_publish http://127.0.0.1/route_to_auth;
             exec ffmpeg -analyzeduration 10M -i rtmp://127.0.0.1/live/$name -strict -2 -c:a libopus -mapping_family 255 ${FFMPEG_FLAGS} -f dash /opt/data/dash/$name.mpd 2>>/tmp/nginx_rtmp_ffmpeg_log;
         }
diff --git a/nginx-transcoder/nginx.conf b/nginx-transcoder/nginx.conf
index 874d7a3..be7d508 100644
--- a/nginx-transcoder/nginx.conf
+++ b/nginx-transcoder/nginx.conf
@@ -16,6 +16,13 @@ rtmp {
 
         application live {
             live on;
+            # Start the exec'd transcoder's input at a keyframe with audio held
+            # until video flows, so both tracks begin together. Without these,
+            # the subscriber gets audio up to one GOP before decodable video and
+            # ffmpeg records that skew as a leading empty edit on the video
+            # track, which desyncs players that drop edit lists in MSE.
+            wait_key on;
+            wait_video on;
             on_publish http://127.0.0.1/route_to_auth;
             exec ffmpeg -analyzeduration 10M -i rtmp://127.0.0.1/live/$name -strict -2 -c:a libopus -mapping_family 255 ${FFMPEG_FLAGS} -f dash /opt/data/dash/$name.mpd 2>>/tmp/nginx_rtmp_ffmpeg_log;
         }