Stop panicking!!! All is well.
One of the U-boat types (Type II I think... I forget which) has this problem... (SH3 stock issue again not caused by GWX)
Try turning the hydrophone wheel or by grabbing the needle and dragging it. One of the two should work.
Rest assured... we did not mod anything to do with the movement of the hydrophone or sonar wheels.
SH3 is full of little quirks... that often we just have to accept and live with.
