All of a sudden, my mags don't fall free when I push the mag release. You have to pull them down, then after you pull them about an inch or so, they hang up again and won't come out until you push the mag release button again! I have 5 mags, and the problem occurs on all 5, so I don't think it's the mag. I've looked down into the magwell with a light and I can't see anything unusual. The gun is about 18 months old and has maybe 2K rounds thru it, with no previous problems. Bad mag release???