jabba sport have had some MEGGA issues lately with the dv30 it seem the older one are ok but if you have bought a new one lately when it get very hot it will jam this is because baileys supplier who makes the nylon type piston the gos inside a changed what they use to make this piston, jabba tested my dv30 by sticking it in the oven....mine is fine as i got mine over a year ago,,...not sure if baily have sorted this yet, just a heads up guys