Multiple Alienware 17 r4 gtx 1080 edition problems

So I bought a brand new Alienware 17 r4 like 2 weeks ago and i began gaming on it moderstely in the past week or so. First issue happened when my alienware was shut off and fully charged but was still plugged in, i turned it on and the usb ports started to give out smoke and burn. So i quickly shut it off and unplugged it and let it cool for a while. After turnin it on I found that the USB ports were fine but the speakers stopped working. Then i started noticing that when i laptop was not plugged into charging, the fps on my games would be around 20 to 30 fps, but whenever i plugged it in they would go up to more than a 100 fps. Im really pissed off because I spent a lot of money on this laptop and all i got is a broken peice of crap.