Review on Hosa CMP 105 Mono Interconnect Cable by Bryan Gilliam

." So the cable is designed to split a mono signal from a 1/4" output to both channels of a 3.5mm input. To use it in the opposite direction (with a 3.5mm stereo output) will add signals, can damage your hardware. If you want to use this as an inexpensive way to connect your phone, tablet, computer, etc. to your speakerphone or sound card, use the accessibility settings to change the audio output to mono.