I got a new Pro-Series M&P40 for Christmas; been carrying it in a IWB holster since then. Last night I went to remove the pistol from the holster to sit in 'my' tv chair; when the pistol cleared the holster I heard a clunk....the mag fell out on the floor. I hope this was just a one time thing. I assume the release button got pushed some how in the holster. Anyone had any issues with this situation?