Hope the OP get things worked out.
I just ran the first 200 rounds, thru my recently purchased 15-22 today. I had absolutely no problems with feeding firing, etc. I paid attention to the posts about careful loading of the magazines with good staggering of the rounds. I used CCI Mini Mags and Mini Mag HP.
Was able to put 32 rounds thru the quarter sized central target hole. The other 18 rounds were very close by. Distance was 50 ft using stock open sights.
My 57 year old eyeballs need some help and I'll put some kind of magnification scope on. The Bifocals screw/blur up the peep sight images...
Very pleased with the 15-22. If I'd had something like this when I a teen, entire generations of gophers would not have existed subsequently. My single shot just wasn't fast enough to get them all....