incorect boosting on gt4, low boost levals on gt4 Options

[droidstar]

hi everyone i have recently joined gt4 ownership owned car a few months and ahve a problem with it, my boost gauge a week ago used to read 10 psi on low boost and 17 psi on high boost, i have a blitz duel sbc boost controler and now boost levals are lower 5spi and jumps to 13 psi high up rev range and on high boost only peaks at 13 psi, i thought i might have a boost leak and replaced all pipes to no difference and wounder wether i have a stivking actuator or faulty boost controler, any help would be greatly appreciated thanks.