When you're traveling or in a crowded place, you probably don't want to annoy others with the music or other audio emanating from your computer. However, if you and someone else want to listen to your system comfortably, you need to connect two separate sets of headphones. Due to the computer only having one audio line-out jack, you may want to connect two USB headphones instead.
Plug the first set of headphones into one of the USB ports on the computer.
Click the "Start" button followed by "Control Panel." Once the Control Panel window opens, select the "Sound" option.
Change the speaker option from the standard "Computer/Laptop" speakers to "Headphones." This makes a headphone connection the current default setting (you can change this back later).
Plug the other set of USB headphones into an available USB port on the computer. You can now listen to the audio from your computer over both USB headphones.
If you only have one USB port on your computer, you can connect a USB hub to the single port. This gives you multiple connections, allowing you to plug in the two different USB headphones.