The P938 is a 9mm is it not? Someone else said 380 and the name makes it sound like a 380.
First things first. There is absolutely no reason to fear max load. None whatsoever. Most max loads are at least 1k psi below max pressure for the cartridge, some as much as 4-5k. A load work up should be done, sure, but all max load is these days is factory powered ammo. Even if the velocity is greater the pressure probably isn't. Staying below SAAMI specs is not "hot", just feared by some reloader who are still feeling things out.
It would be more helpful if you told us the exact powder and charge you are loading. Also OAL isn't ever going to be a factor here because by the time the barrel unlocks from the slide all that is left is the ejecting brass case.
But that being said it may well be the gun because any 100% functional gun should run on WWB. If the problem was lesser the second time around it could be a gun working through some break in problems. My advice is to work those reloads right up to recommended max, leave the OAL alone because it isn't the issue and make sure the gun is well cleaned and lubed when you shoot it. Hold that little thing very firmly also. If it isn't meeting your expectations at that point I'd point the finger at the gun.
New gun, same ol' shot.