I purchased a new Mark IV Competition about a week ago and have put about 300 rounds through it. From the very beginning, the magazine will pop out during firing, causing a misfire and/or jam. This happens usually about round-3 or 4 of every re-load, and happens with both magazines. It has gone an entire clip without misfiring, but only a couple of times. Have to manually hold the magazine in to prevent the issue. Has anyone else had this problem, and can you recommend a solution? By the way, I have completely removed the magazine ejector spring, and this seems to have temporarily solved the problem, but that does not seem to be the correct long-term solution. Any ideas? Thank you!