so ive just had a go at tuning my kit to make them more sensitive, i can see why they sent then being a little under sensitive, i put all the pads on 20 which is the max setting and the symbols were getting set off when i hit the drums and vice versa,so thing i found the right balance.
got my symbols on 15, they set each other off very easily, got my red on 13 as it seemed to be set of from the yellow on occasion, got the blue and green on 15 which are fine with the orange.
gonna have a play and prob fine tune a little more, but over all i only needed tiny adjustments.
the symbols need to be hit in the center at the top right as thats were the sensor is, even at max sensitivity near the edge sometimes doesnt get picked up.