Same issue, different possible explanation
"I did have a few failures to feed but I blame is not on the action or design, but a faulty magazine catch. Mine is REALLY sensitive and barely touching it will release the magazine. A few times I'd accidentally release the magazine and because the mag was slightly dropped it wouldn't feed. A slap and rack would fix it. I already contacted CZ and I'm going to send in my magazine release for modification."
I had exactly the same issue with a glossy blue CZ-97B pistol when firing commercial Fiocchi .45 ACP ammunition. When I began using my handloads, I worked up to 5.4 grains of W231, I had no problems whatsoever using 5.0 grains (very accurate and very mild recoil). Based upon my experience with the handloads, the Fiocchi ammo was at least as hot if not hotter than my 5.4 grain loads (reduced accuracy and painful recoil)! I think this brand of commercial ammo literally jars the magazine loose, at least on every other round I fired! I have not tried any other commercial ammo, so I guess it is still a possibility that the magazine needs tweaking. But, for me, I am sticking with my handloads.
Tim
P.S.- I have an RSR special CZ-97B in satin nickel due to arrive tomorrow! I will try and post some pics next week.