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Unfortunately, at this time, closed caption is not supported for MPEG-DASH streams in Wowza. This is on our product roadmap and planned for this year, although I cannot guarantee this time frame. I have made sure to forward your use case to our Product Manager, to ensure that the prioritization for this feature request is updated.
Please do check back in periodically to our Software Updates page to see if your feature request has been deployed.
Thanks for the response. We have a project trying to migrate to Dash. Right now stuck with clunky HLS.JS. Client is constantly asking about it and insisting it work I’m afraid. What is the issue exactly ? I am fairly certainly an early version had 608 captions working with dash.js.