Amazon.com: TENEALAY 4-Way 3.5mm Stereo Audio Switch Input Signal Source Switcher Selector Splitter Box with line Volume Controller (4 in 1 Out / 1 in 4 Out) -MC41 : Electronics
PC Speakers/Headphones Audio Switch Converter Volume Controller for Switching Back and Forth between PC Audio
2 Way Audio Switch 3.5mm aux Source headphone speaker switcher selector Box - M1 | eBay
Best budget computer speakers: $100 or less | PCWorld