User guide
Command
ASCII Command 
(host to switcher)
Response 
(switcher to host)
Description
Switcher-
initiated 
messages
Program audio ducking level in talk over mode
Adjust audio ducking level
X1@
 * 58# Adl 
X1@
]
Adjusts how much 
(
X1@
 = 0 to 30 dB) the program 
audio ducks (automatically 
decreases) in talk over mode. 
0 = ducking off.
Increment audio ducking +*58#
Adl 
X1@
]
Decrement audio ducking –*58#
Adl 
X1@
]
View audio ducking level 58#
X1@
]
Volume level
Specify volume variable
X1)
 V/v Vol 
X1)
]
Volume level is 
X1)
.
X1)
 = 000 – 100 (program 
volume adjustment range).
X
Increment volume +V
Vol 
X1) ]
Volume level is 
X1)
.
Decrement volume –V
Vol 
X1) ]
Volume level is 
X1)
.
View volume V
X1) ]
Volume level is 
X1)
.
Audio mute
X# 
Z/z Amt 
X# ] X#
: 0 = off and 1 = on.
X
View audio mute status Z/z
X# ]
Mute status is (0=off, 1=on).
Mic level
Specify gain
16* 
X$
G Aud 
X$
] X$
 = audio gain in dB = 0 to 
12. This variable is a positive 
number.
X
Specify attenuation
16*
X%
 g Aud 
X%
] X%
 = attenuation in dB = 1 to 
66. This variable is a positive 
number.
View mic volume 16G/g
X^
] X^
 = overall mic gain or 
attenuation between -66 dB 
and +12 dB. This response 
variable indicates attenuation as 
a negative number and gain as 
a positive number.
Mic mute on/off
Turn mic mute on/off
X# 
M/m Mix 
X#
]
Toggles mic mute on or off. 
X#
: 0 = off, 1 = on.
X
View mic mute status M/m
X#
]
Mic mute status: (0=off, 1=on).
Mic talk-over threshold
Display talk-over threshold
X*
 * 2 # Thr 
X*
]
Shows the mic threshold 
number. 
X*
 = 0 through 15, 
default = 8.
Decrement threshold  – * 2#
Thr 
X*
]
Decrements mic threshold one 
step.
Increment threshold + * 2#
Thr 
X*
]
Increments mic threshold one 
step.
View mic talk threshold 2 #
X*
]
MPS 409 • SIS Programming and Control 24










