Ok so today I think I figured out my problem, I unscrewed completely the give screw (with an Allen key) and the spring pinged off, put it back on the machine and screwed the give screw back on and to my surprise I had a real soft hitting machine! Now I feel pretty stupid that this is all that the problem was. It seemed the spring wasn't sitting right for whatever reason and as soon as its gone back on properly it's running perfectly. I can't believe I didn't try that sooner, I think I was expecting something more complicated.
i tattooed a black and grey piece and was pretty happy with the results and softness. It definitely made me speed up compared to when I use the dragonfly which is great because I tattoo really slow usually!
Thanks to all your comments and advice, at least now I know if I have a problem in future I just need to look for the simplest problem first or just ask you guys!