a Input buttons — The input buttons have one primary function (❏) and six secondary
functions (•):
❏ Select and identify an input.
• (Input 1 only) With the Output 1 button, select I/O Group mode.
• Assign an input to the selected group in I/O Group mode and indicate its
assignment.
• Select a preset.
• Display the output volume level.
• Select and identify the audio/RS-232 wire pair as audio (unlit) or RS-232 (lit) in Serial
Port and Audio/RS-232 Input Configuration mode.
• (Input 1 and Input 2 only) Toggle background illumination of the buttons on and
off.
b Output buttons — The output buttons have one primary function (❏) and five
secondary functions (•):
❏ Select and identify an output.
• (Output 1 only) With the Input 1 button, select I/O Group mode.
• Assign an output to the selected group in I/O Group mode and indicate its
assignment.
• Select a preset.
• Mute the audio or RS-232 output..
• Display the audio level of the selected input.
MTPX Plus Series • Operation 25
