The Comms Preferences panel is used to choose the Midi and RS232 interfaces
for communications with an equaliser.
To enable Midi port selection check Enable Midi, Midi port selection is disabled by default under macOS as Midi access causes the Java Runtime Environment to crash on some Macs.
Choose a Midi Output Port if using an equaliser with a Midi interface which REW supports. BFD Pro DSP1124P and FBQ2496 can be programmed by REW via Midi, refer to the BFD Comms help for details of setting the units up.
RS232 Ports are only supported on Windows and are only used with the TMREQ equaliser in AV32R DP and AV192R AV processors. Refer to the AVP Comms help for details of setting those units up.
Note that only ports that existed when the Comms Preferences tab is first opened are available for selection, a restart of REW is required to detect Midi or serial interfaces that were connected after viewing the Comms Preferences.
The FBQ Filter Delay setting controls how long REW waits between each filter set sent to the FBQ2496, if transfer of filter settings is unreliable increasing this delay may help.