previous song broken?

It is my or does the previous song option not really work? It seems to restart the current song both in the UI and from the command line interfaces (both mpd and the volumio command line), In the UI, if I’m quick and click previous twice I can get either the previous song or the one before that (so previous or previous -1) but I cannot reproduce a reliable previous song action through the CLI options (mpd and volumio). Is this behavior by design or is it broken? Thanks in advance.