Subtitle Delay Issue with Cloudflare Stream and VideoJS (DASH Playback)

HI,

I’ve encountered involving subtitle synchronization during video playback. This issue specifically arises when using Cloudflare Stream in conjunction with VideoJS, and it appears to be isolated to DASH streams.

Issue Description:

  • While playing videos on VideoJS that are integrated with Cloudflare Stream, there is a consistent subtitle delay of exactly 10 seconds.
  • This issue is exclusive to DASH streams. When using HLS (HTTP Live Streaming) with the same player setup, the subtitles are perfectly synchronized with the video.

Possible Cause:

*I’ve noticed that the X-TIMESTAMP-MAP value is set at 900000, which equates to a 10-second delay. This seems to correlate directly with the delay issue observed during DASH playback.

Is there anyway I can remove the value from X-Timestamp-Map?

Thanks

@sipher1975 — thank you for reporting this! Can you please try reproducing in the DASH reference player and let me know if the issue is present there as well?

Also, if you’re able to share the video ID that you’re seeing this with would you mind sharing either here or email me — kkipp-at-cloudflare-dot-com?

Hi kkipp, We have reconfigured VideoJS to exclude the following content when using DASH streaming:

X-TIMESTAMP-MAP=MPEGTS:900000,LOCAL:00:00:00.000

This metadata is a standard for HLS, but it appears to affect VideoJS in some way.

Hi kkipp, we couldn’t eliminate the following code from the VTT file processed by Cloudflare. We’re utilizing VideoJS alongside the VHS plugin (videojs-http-streaming). Is there a method to remove this from the VTT file through Cloudflare, so no 10 sec delay in subtitle or do we need to address this issue on our side?

X-TIMESTAMP-MAP=MPEGTS:900000,LOCAL:00:00:00.000

Below is the demo page to show the 10 seconds delay
Demo Page

We recompiled VideoJS, the problem is now solved.