I've had new shells that wouldn't fire.

Lucky for me, they were Winchester shotshells, and this was at the Grand American trapshoot, so when I brought the misfire to the Winchester rep they gave me a whole new box of shells [img]/forums/images/icons/smile.gif[/img] and thanked me for bringing it to their attention.
Now, thats customer service.

I would bring the misfires back and raise stink.

I think I read somewhere that some Ruger 10/22s don't like some finds of ammo, but I don't remember the version of the 10/22 or the ammo. Its the ammo's fault, anyway.

Just in case, it is possible that the firing pin or the hole it fits into is plugged up a tad. If the pin has a 'shoulder' their could be crud or corrosion which prevents the pin from striking fully. Similarly, especially with a semiauto, the bolt may not be closing 100%.

I know you just had the gun cleaned, but mistakes happen.