i dont know how to explain the problem with my mechbox. i put the first mag in and flicked the lever to semi and aimed and fired at the target and nothing came out so i was like ok maybe misfeed took themag out and tried another mag still nothing making noise that it is shooting nothin coming out so then i take the silencer off and see if i causing that. tried shooting again and finally it shot something. go again and its shooting fine then i switch to full and it gives a little burst of 3 bbs and i was like ok it works not . switch back to semi to lessen the tension on the spring from full auto and thats when it mad a werid grinding noise and locked right up. it makes a noise when u pull the trigger but no movement of anything in the mechbox. chekced the battery and it is fine then checked the mags i used on my other friends aeg and the mags worked fine. hopefully that explains the problem i will no forsure when i get it repaired.