Youtube-dl warning message
Downloading a tracks from youtube, I often get this warning
message:
WARNING: You have requested formats incompatible for merge. The formats
will be merged into mkv
However the resulting mkv file neither shows the vid nor do I hear the
audio.
The player is latest mplayer.
$ youtube-dl --version
2015.05.10
Does mkv need any special codecs that I do not have?