95 per-cent of the time when a gun has problems feeding it is the magazines. Does this happen only on one mag or several.What types of ammo are you using? Is this a new firearm ( to You ) or has it happened before?
A buddy of mine carried a standard Browning P35 for years, and it functioned flawlessly with ball ammo. Fed and fired first time, every time. And then Super Vel introduced their whoop-dee-doo hollow points. My buddy buys a box, we take his pistol to the range to try out these wonder rounds, and CLUNK! Nosedive jam first round off the top of the mag, and all following rounds on both that mag and his spare. He went back to ball ammo, his reasoning being that if 13+1 ball rounds didn't solve a problem, Super Vels wouldn't either. That said, what type of rounds are you using?