I checked in here about a month ago with issues with my M&P22 that appeared to be the sear/hammer engagement. I contacted S&W service and sent it back for repair. They replaced the plunger and I had the gun back in 2 weeks from ship out to return and they gave me and extra 12 round magazine for my troubles! Easy to deal with and fast work in my book. Gun is A-OK now.
Tony
Tony