Choose a compatible desktop player
Ask support about the access methods your selected player accepts. Obtain the app from its official publisher rather than an advertisement or a bundled download site.
Use the right input field
A playlist link normally belongs in the playlist or network-stream field. A server login requires a player that accepts separate address, username and password fields.
Check the whole playback chain
Try built-in speakers before troubleshooting external audio. Compare a few channels, a movie and available subtitles. One title alone is not a complete test.
Keep links out of public tools
A playlist URL may contain your username and password. Never paste it into public validators or issue trackers. Share error messages with support after removing private details.