Don't loop unplayable items indefintely
When opening a file which can't be played, or trying to open a stream but giving the wrong address, VLC doesn't just throw an error, it keeps trying over and over and keeps throwing the same error.
If there is no playable item on the track-list, instead of continuing to the next item, stop playback. This applies to both having one unplayable item on loop, or having multiple items all of which unplayable.
Additionally, if an item cannot be played, and VLC is set to loop, ignore any items which have already been recognized as unplayable when looping. There is no point in coming back to something which doesn't work. Just mark the item in red, so the user can see it won't play.
Finally, add a checkbox in preferences: "do not ignore items which initially seem unplayable". This option will disable the suggested changes. This can be useful, when the user is setting VLC to retry opening a stream, and is waiting for the server to start. Although it isn't ideal to do it by looping. (better ideas to do that?)