It's not the gun, it's the nails. The points are cut differently, depending on the type of nail--brad or finishing--, and the cut angle causes the shank to deflect in a particular direction, almost every time.
Brad nails will deflect side to side--across the head of the gun. When you use them hold the gun perpendicular to the board into which you are nailing (man, sometimes proper English is awkward).
Finishing nails will deflect front to back--in line with the gun. When you use them hold the gun parallel to the board you are nailing into.
The best thing you can do is get a piece of 1/2" scrap and blast a series of nails into it, turning the gun in different directions until you get the pattern of whatever nail you're using. As a backup search WOOD Magazine for "Avoiding Nail Blowout". It should direct you to a couple of articles. A universal search will probably turn up multiple articles and videos on this.
FWIW I learned this the hard way too. It's a bear nipping, countersinking the exposed tips with a punch, and patching the indentations with filler. Not what you want to be doing when you're making fine furniture.