I have a CYMA 1928 thompson and the gun had been functioning fine up until a few days ago. First the drum mag would not feed correctly, and now it wont shoot ob semi auto correctly. The magazine is a problem I can live with considering they are replaceable, but I use semi auto the most to save on ammo and now it will get on sucsessful shot on semi and the rest will be bursts of 5 shots to even 20 shots. It is too unpredictable and I need to get it fixed. I took apart the gun and the internals seem fine and I called the manufacturer but I had to leave a manufacturer. And it cant be the battery because I put it in my M-16 and it worked perfectly. Any sugestions would be very appreciated and thank you.