Alesis Studio 12R Reference Manual page 45

Hum or noise from
output.
No meter, although
audio is heard
through main
outputs.
Crackling sounds.
Studio 12R Reference Manual
Ground loop,
unshielded cables.
Monitor switch is
set to "TAPE"
Dirty or corroding
connections on back
of mixer.
A microphone cable
has a small short or
break.
Troubleshooting
Try plugging the unit
into another power jack
or different audio cables.
Set switch to "MSTR"
Unplug and replug
connectors sev eral tim es,
clean plugs.
Unplug the microphone
cables from the mixer
until the noisy one is
found, and replace it.
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