Use the wiring diagram shown below. It is important that all of the connections are made, otherwise there could be a loss of input signal level (e.g. XLR pin 3 left floating) or induced hum (e.g. chassis ground and audio ground connected together) due to ground loops.
Please note: do not connect the XLR chassis to XLR pin 1, as this will compromise the RF immunity of the monitor's electronics.
Wiring diagram for TRS Jack output to XLR input using 2-core and screen microphone cable.