Are you ready for a different diagnosis? I have recently dealt with the same problem in other similar magazines. Yes, it could be the magazine and a lot of the times it is, but not always. I am a believer in not filling any magazine to max capacity so I had never had that problem in the past until just recently I had a feeding problem with the first round in a magazine loaded to max cap but the remainder fed well.
The top round is under more pressure than the rest and when a recoil spring in a pistol (or buffer spring in a rifle) is just short of enough strength to completely push off that top round into the chamber then you need to strengthen, however, not over strengthen to the point of not cycling the BCG or slide. So, if the rest of the rounds in the magazine worked fine then WHY? I would think there`s nothing wrong with the magazine and look for another cure.
SO, was your pistol set up to load 8 round magazines? I say try another brand of magazines and the spring tension on the follower may be that sweetness to make a flawless performer.
If the same problem exist then maybe a heavier recoil spring. Are you pulling the slide all the way back and letting go or babying it? You load the first round to duplicate how the slide will load the rest of the rounds. Just .002" difference in the wire diameter of a spring could make a world of difference how your semi-auto works. There are more ways to tune a 1911 than any other pistol in the world and when they`re right....they`re right. Same with AR`s when experimenting with different calibers and magazines. Make your adjustments with moderation taking small steps at a time.(Also, there`s a lot of selections for progressive-wound aka "enhanced" springs for the max cap mag shooters whom are the "violin player" class of shooters)