Unresponsive or slippy? these are two different things that many people seem to miss.
Unresponsive -> string not rolling or don’t roll enough when you tug it up.
Slippy -> string rolls when tug up, but it doesn’t grab/lose grip.
If it’s unresponsive, try using different string, different wood, make the groove on the wood bigger (diameter).
If it’s slippy, it’s the response pad.