Star B were built for 38 Super/9mm Largo/etc but usually chambered for 9x19, shorter cartridges than 38 Super. Therefore, there is space in the magazine for cartridges to move forwards and back. They commonly nose dive, usually first or second round, as the magazine is too long for the 9x19, usually also with the 9 shot mags. Yes there are 8 and 9 shot Star B mags, check the followers for difference. Very frustrating jam when you're shooting IPSC.
Load mags, tap back against solid object such as table, boot, etc to settle the rounds at the back. That usually works. Or just get used to it.
Clean mags, using a brush from the top, slightly oil if possible.