Gaz,
The hack for the JMB 3000 is as you know Power up, Press Stop, Open, Close and skip forward for 4 seconds then you should get the Hidden menu. A mistake some friends of mine have made with regards to this DVD player hack is pressing the buttons on the remote to try and get the hack when infact you need to press the buttons on the player to get the hack. If you still get no joy then you might have bought the newer version of this player which as I remember has a slightly different hack. Let me know if this helps.
DUSTY