Help with jumpin jack flash

[mark_the_destroyer]

Hi was wondering if any 1 can help me im new to fruit machines but have bought a used jumpin jack flash.i have managed to fill the hopper using refill key with £125 and all works ok but the only problem is it pays out really easy all the time it says on front 78% payout but any bandit ive played never played this well is it something i could ave done pls help as i dont want my mates coming round n taking all my money