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Section 9: Trouble Shooting
Symptom
Likely Cause
What to do
No sound
No Power
Make sure that the AC cord is properly seated into the AC receptacle
both at the wall outlet and on the mixer. Make sure the AC switch is in
the "ON" position. If you are using an "AC Strip" check to see that it
is working properly.
Volume’s are turned down
Make sure both the mixer’s channel volume and master volume are
turned up. Double check to see if the source volume is turned up.
Mechanical connections
are loose
Check to see if the input to the mixer is properly seated.
Check the speaker connections to see if they plugged in all of
the way.
Bad Cables
Your speaker cables may have been damaged. Inspect for any cuts
or crimps and if found, replace the cables.
Phantom Power is off
If you are using a "Condenser" type microphone you will need to
activate the "Phantom Power" switch for the microphone to work.
Sound is distorted
Input overload
If the "Peak LED Indicator" is flashing red or on constantly you may
be overloading the input. On channels 1-4 turn the channel volume
down and press the MIC/LINE switch. Slowly bring the volume up. If
the distortion is gone but you don't have enough volume, turn up the
master volume.
If you are using an external device like a personal music player or
electronic instrument try lowering the volume on that device.
System is overloading
Check the “SYSTEM LEVEL INDICATOR” LED’s and if the “LIMIT”
or red light at the top of the ladder is on constantly you may be
overdriving the system. Turn down the MASTER VOLUME.
Sound is thin
Too much treble
Check the channel's "TREBLE" control and turn it to the "0" position.
Not enough bass
Check the channel's "BASS" control and turn it to the "0" position.
Speakers not
connected properly
Check the speaker connections to see if they plugged in all of the
way.
Effects levels may be too high
Try turning down the MASTER EFFECTS RETURN.
Sound is too boomy or dark
Not enough treble
Check the channel's "TREBLE" control and turn it to the "0" position.
Too much bass
Check the channel's "BASS" control and turn it to the "0" position.
Hum or Buzz that increases
or decreases when the mixer
level controls are moved
Improper A/C ground or faulty
equipment connected to
mixer input
Disconnect or mute channels one at a time to isolate the
problem. Refer to the owner’s manual of the faulty equipment for
troubleshooting help.
Faulty cable between source
equipment and mixer
Substitute a known-good cable for the suspected faulty cable.
Hum or Buzz
Improper A/C grounding,
ground loops
Try using a ground lift adaptor. Connect all power cords to the
same power strip.
Excessively long unbalanced
cable run
Try a shorter cable if possible, otherwise use a DI box to
convert the unbalanced signal to a balanced signal and use
the appropriate cabling.
Improper system gain structure
Reduce the INPUT level controls and increase the output level of
your source devices.