hardware - Wiring an XLR 1/4" jack combo wall box to a single cable (Neutrik ncj6fi-s) - Sound Design Stack Exchange
CARDINAL DVM Central unit, Central unit including beltpack, IN: 1 x Stereo IN via 2 x combo XLR / jack bal. incl. level switch/1 x Sub IN via combo XLR / jack
File:XLR-phone jack combo connector.jpg - Wikipedia
3-Pin XLR with 1/4" Mono Jack Combo Socket Chassis Metal - China Audio Connector and Cable Connector