Hello Jollster101. It sounds like you have overfilled your gas cylinder. So if you are talking about these cylinders here:
https://www.kegland.com.au/450gram-...illable-gas-cylinder-for-co2-or-nitrogen.html
on the side of the brass valve you will see a small hex nut. Under this hex nut is what we call a "burst disk". If the pressure gets too high you can burst the disk. This is a safety feature installed to the cylinder to prevent the cylinder exploding. The the burst disk blows open it goes with a loud bank followed by a hiss than will probably go for about 60 seconds or something. This is designed to release the pressure in a controlled way. (relatively speaking, far more controlled than the cylinder exploding).
Every year we hear of a hand full of burst disks blowing on not only the
Sodastream Cylinders byt also the
6kg cylinders and
2.6kg cylinders. This generally happens for two reasons:
1. The cylinder is overfilled
2. The cylinder gets too hot (ie goes above 40C)
Is it possible that either of these things has happened?