Amazon.com: Audio DTS Converter, 5.1 CH RCA Digital Fiber-Optic Coaxial to Analog with Coaxial Cable for Vga Monitors, TV Boxes, Power Adapters, 5.1 Audio, Projectors - Black(us) : Electronics
Digital Optical Coax S/PDIF Audio To 5.1 Analog Surround Sound Decoder - Walmart.com
Source SIPU Good quality factory supply rca to rca cable hdmi to 5.1 rca cable on m.alibaba.com
Amazon.com: Replacement Audio Cable Compatible with Logitech 5.1 Channel Computer Speakers Color Coded 3.5mm Minijack 3 Male to 3 Male 6.5ft,Compatible with logitech z-5500, z-5450, z-5400, z-5300, z-906, z-680, : Electronics
Amazon.com: Ancable Replacement Audio Cable for 5.1 Channel Logitech Computer Speakers 3.5mm 1/8 TRS Plug Male to Male 6ft,Compatible with logitech z-5500, z-5450, z-5400, z-5300, z-906, z-680, x540 etc. : Electronics
Amazon.com: VAlinks USB 2.0 External Sound Card 6 Channel 5.1 Surround Optical S/PDIF Audio Sound Card Adapter for PC Laptop Recording Compatible with Windows 10/8 / 7/ XP : Electronics