KMCng - "No source video was found"

If I upload a video to be encoded. In the new KMC (HTML5) show error “No source video was found” appears which is normal while the source does not exist. When the source is already up and the profiles are being encoded, you still see the error message “No source video was found”. When the first flavor is coded is when we stop seeing the source error. If I delete the flavor created, it still works

Note: When the error occurs, If I see the preview of the flavor source, it works.