A-5 flatline Barrel trouble

My flatline barrel for my Tippmann A-5 tends to fly out of its fake silencer housing.  Im just wondering if anyone else has experienced something like this before, and also if anyone has any suggesstions for me.  This could be a potentially dangerous problem if I was running up on some one and shot at them point blank, (instead of getting hit by some paint they could get hit with a metal barrel instead), and the end of the barrel has a pretty sharp edge.  So if anyone has ever experienced the barrel falling out or even practically flying out please give me some feed back.  Oh and by the way my velocity is not very high at all and well below the field regulation.  I know for sure because I was playing with my little brother on a really hot day so we turned our feet per second way down, so we could just wear a tee-shirt and shorts.