CEA-608 recorded from dynamic manifest, do not have time approximation, when converted to static manifest

[ZygmuntMalek]

Environment

• Link to playable MPD file:
  not have at the moment as content is at closed environment

• Dash.js version: every ( also 4.7.4 )

• Browser name/version: not important

• OS name/version: not important

Steps to reproduce

1. When play dynamic manifest with CEA-608 closed captions
2. Manifest is converted to static ( in case timeshif tv ) ( stream is not transcoded )
3. When play static manifest CEA-608 cues have dynamic timestamps, they are not approximated as manifest is static now, closed captions are not displayed

Observed behavior

Closed captions are not displayed

Expected behavior

As after transition from dynamic to static, dynamic timestamps are ignored during playback, CEA-608 timestamps also should be approximated to get it static value