tvheadend 4.2 and missing ATSC closed caption on recorded content

Hi,

With the recent Millhouse LibreELEC nightlies and tvheadend 4.2, I am recording ATSC OTA broadcasts.

If I watch live TV, ATSC closed captioning works. When I playback recording content, closed captioning does not work "teletext not available". When I used VLC to playback recorded content from the tvheadend web backend via .m3u file, closed captioning in VLC works fine.

So the recorded content kept the ATSC closed captioning, and clearly LibreELEC can show them with live TV, has anybody gotten ATSC closed captioning to work with the tvheadend PVR client for recorded content? Would this be a Kodi 17 issue?

Thanks