Things You'll Need
Instructions
Connect the red and white audio plugs to the 3.5mm female adapter. If you do not have the needed adapter, one can be purchased at your local electronics store for a reasonable price.
Plug the adapter into the "Microphone" jack on the back of your computer. It is typically the pink-colored jack, and will have a picture of a microphone beneath it.
Turn on the computer and access the control panel once the operating system has loaded.
Double-click the "Sounds and audio devices" icon to open the needed window, then click the "Advanced" button under the "Device Volume" section.
Click the "Options" menu button, then select "Properties" from the dropdown menu.
Scroll through the list in the lower portion of the new window that pops up until you see the "Microphone" option. Make sure it is checked, then click "OK."
Check to make sure the Microphone volume is not muted in the volume window you return to, then click the "advanced" button under the "Microphone" volume setting. Ensure that the "Microphone Boost" option is not selected.
Turn on your Xbox 360. The sound will now come through your PC speakers. Adjust the volume on your speakers to your taste, then click "OK" to close out the windows on your computer.