On debian 8 i had no problem with Juk, on debian 9 it loads playlists and songs but when i press play it doesn't start the reproduction, dont'k know why
It almost sounds like you don't have the right media codecs installed after the upgrade to Debian 9. But it could be anything; this bug report doesn't have enough information in it for us to triage. I suggest getting help via a Linux or KDE support forum, and if there is a real KDE bug (as opposed to a misconfiguration, distro packaging issue, or distro upgrade issue) it will become clear, and you can file a new bug.