The RIA magazines are kind of hit and miss from the factory. So definitely try with new mags. My first 1911 was a RIA and did the same thing out of the box. It was a mix of break in and mags.
Also I'd say it sounds like break in is needed. Take the recoil spring and guide rod out (if your model has a rod) thumb the hammer back, and move the slide through a full motion. Straight up like it should be shot and tilted 90 to either side. Mentally note anywhere that slows down or feels like it is binding/dragging.
Personally I just take some flitz, put it on the rails, and then cycle the bastard ~50-75 times. It's not aggressive enough to remove real amounts of metal (particle size is 3.5 micron or so. Simichrome is 8-10 micron) but it will smooth out the high spots a bit.
That said, this is the internet, do your own research, I make no warranty on doing the above action, your milage may vary, if your erection lasts longer than four hours please see your doctor, take a grain of salt with this post, etc.