I had a programmable shunt placed five weeks ago. I have three settings and have had to be adjusted to all three! The setting the doctors have settled on is too low and I still have a headache! The doctor has mentioned putting in a different shunt with 21 settings so he can dial in a more accurate setting for me. I have tried to just live with the headache I have to avoid yet another surgery... but I don't think I will be able to take it much longer. The adjustments I have had so far have been interesting... like the other person mentioned earlier, you can hear the shunt changing. It's a strange clicking noise. I felt an odd sensation (not painful) when it clicked. Hope this helps.