hi, i have a bt-4 and today when putting my co2 in i heard a hissing sound that i havn't heard before... i fired off the gun and took the tank out as soon as i heard this, when i put the tank back in there was no hissing but when it came to taking the tank out co2 started coming out the bleed hole on the ASA adapter. i decided to try again and the tank started hissing whilst putting it on aswell as taking it off... i then tried one more time with no issue? is this a problem with the gun or the tank? is it worth worrying about? any help appreciated