That did the trick. Big thanks for help.
BTW since the name potplayer was mentioned do you have any experience with this player? I really would like to use it to play Youtube but I am not able to solve similar problem with playlists I had with mpc-hc.
If the command executed looks like this:
PotPlayerMini64.exe <video_url>\"Title" <audio_url> /same /current
potplayer opens and plays both video and audio correctly. But it adds to its own playlist only the video stream. One can check this simply by double-clicking on this playlist entry which restarts playback. And this time only the video is present, not audio.
I have experimented with potplayer's own playlist files (*.dpl) but I'm simply not able to format them the way the player sees both streams as one and plays them at the same time. I succeeded with mpc-hc but not this time. It a pity because I like potplayer's thumbnail previews on navigation bar a lot. On the other hand potplayer's own build in youtube engine causing frequent Youtube's blacklisting "due to suspicious activities". SVP Tube is much better with its built in cookie support which prevents that. But is it possible to connect both of these two apps the way the potplayer's playlist works correctly?