You're lucky you didnt have to talk to him directly.
I have a similar issue in that I bought one 2 years ago, never worked past 2-3 rounds, just like yours. Got sick of it, and put it away, got busy with new baby, no money to shoot etc. Took it out recently and tried in in my new AR. Same problems. Read a lot on ARFCOM about adjustments, springs, tweaks that might fix the problem. Those didnt work. Called Ceiner to see if THEY had any tweaks or changes to the system that might help. Mr. Ceiner answered the phone.
He was the rudest nastiest person, that is selling his goods, that I have EVER dealt with. He insulted me, harassed me for not sending it back when it was under warrantly and was incredibly nasty. He took extreme offense by me simply asking if there were new springs or tweaks to his system since I bought mine a few years back. He insisted the system was perfect, asked if I was using the propers ammo, I was, and after a few minutes of berating, hung up on me.
I plan to unload it at a gun show soon, or maybe trade it for something. I may try the heavier springs first. They dont cost much and I hear they fix the jam problem.
Not sure it will though, cuz when mine james, it bends the bullet in the casing.
Took some pics of the rounds and planned to send them to ceiner, but decided he wasnt even worth the $.37.