STEINBERGER DB BRIDGE - Detune Issue

[xverminate2]

Hi All !

I recently purchased a second hand Hohner B2A bass. It has the DB bridge fitted.
My problem is that I am not able to detune lower than "D#".
I found a PDF nammed "Steinberger DB Bridge User Guide" on the internet that confirms I was doing the right procedure. I tune the E string as normal, using the rear thumbscrew, whilst the detune leaver facing forward towards the fretboard.

1.To set the drop tuning, I Flip the leaver towards the rear of the bass.

2. I then turn the top thumb screw anticlockwise to detune but it  will not go any lower than "D#".

3. Then when I return the flip leaver to the normal E tuning position, nothing happens, it is still at the D#.

Any ideas ?
Thanks !

Greg