Hi!
Check
www.electricstart.de . Some pictures there how to connect (this version for optical devices, but do also work with coaxial plugs (put a serial resistor of 390 Ohm into each output line and connect this to another resistor of 91 Ohm and connect this one to GND. Output then is the connection between both resistors as the hot point and GND for Ground).
See the little picture left down in the big picture.