I've shot my Sig 716 about 3 times now. The first 2 times I think I had one FTF out of about 200 rounds. The 3rd time to the range I installed a PWS FSC30 compensator. This time I was having FTE almost half of the time. The brass seems to be getting caught between the top of the ejection port and the next round in the magazine. I haven't cleaned or oiled the gun yet. There seems to be some debate as to whether you even should clean an AR as opposed to just oiling it occasionally. After having the problem I did pull out the gas piston and it didn't have much carbon on it but I noticed there was no oil at all. So I cleaned it with some CLP. I've done a little research and it seems you sometimes need to adjust the gas flow for a compensator, but there are only 4 settings on the 716. I noticed that it locked open every time on an empty magazine, which leads me to believe it's getting enough gas. Any thoughts?