Instruction: Answer the given question using the supporting document.

Input:
Question: What is the USB plug-in for? Do you plug the headphone,mic,and USB plug-in all at the same time? thanks!
Document: No problems so far. Good product, has volume on head set, make sure you plug the power cable in first (USB). Had a little problem with the mic during gaming. IDK what the problem was but it has seemed to work it self out now.
This headphone is sweet... looks super cool and sounds awesome. The USB is only for the lights. The cord is really long which becomes really handy. Worth more than what I paid for. 5 stars. :)
Ok so it could be my head? But I don't know. Feels like the top of the speakers our sitting to far from my head and I cant adjust to get it to sit closer.But for the price, great audio out and in! I love the optional LEDs as all you have to do to not use them is not plug in the USB connector. The cable from the headphones is thick and long just the way I like it.
This seller placed a misleading ad about this product! They did this to cover up the fact that to make all of the features of this product you would have to use three ports on your computer. This is a poorly designed Headset because it hogs the resources of your computer when all they would have needed to do was to combine all of the connections into the available USB plug as their competitors have done. Save yourself the trouble and buy something else! WASTE OF YOUR MONEY, TIME AND EFFORTS!
The Headset came in very nice packaging, had Japanese writing supposing its imported from Japan. This headset does not require the usb to work, plugging in the 3.5mm jack into an ipod without USB still works as well as the mic. The usb only powers the device so that it lights up. The mic is very weak, have to put it close to mouth. Comfortable for small ears. Decent.
This is the first headset i have purchased, and my experience before that is the mic that came with the Xbox 360. so the sound is quite a step up from that as is the mic.my problem with it however is the size of the pads, is a little small, leaving my ears a little sore after longer game sessions. this is something that i hope goes away with time.other than the size issue this is a great buy.
The blue lighting is powered by the USB 5V, so if you don't want it lit, just leave the USB unplugged. There is a volume control on one of the earpieces, but it is analog, so it won't actually turn the system volume down, only limit the volume going into the headset.
I absolutely love this headphone, it's light so my head doesn't feel like being weighed down by tons of bricks. The lights were just a big bonus that makes me look awesome while gaming at night! All my friends are envy of me having this headset. I do recommend this headset for any beginner or intermediate players!
It's very comfortable, however, sometime I have problem trying to talk to people since the mic always seem to be low.
Awesome headset but the mic broke after only 2 days of use so I had to return it. Too bad its a cool looking headset.
Answer: You can use the usb or the other 2 plugs there is no reason to do both. The other 2 i believe are for people who dont have enough usb slots or perhaps so you can listen thru your speakers and talk thru the mic.