Troubleshooting - Yamaha DDK-7 Owner's Manual

Troubleshooting

Problem
GENERAL OPERATION
The sound is not heard for about 10 seconds after
turning the power on.
A cracking noise is sometimes heard.
Interference from radio, TV, or other sources occurs.
The sound of the DDK-7 causes surrounding objects
to resonate.
In the LCD display, there are some black points (unlit)
or white points (always lit).
The sound is too small even when the volume is set to
its maximum.
Foot Pedals has no effect.
The DDK-7 panel does not function normally or the
content of the memorized data has changed.
The Pedal Unit does not work.
Some parts cannot be heard from the Headphones or
an external speakers.
Possible Cause and Solution
This is normal; the DDK-7 takes a while to start up.
Noise may be produced when either an electrical appliance is turned on or an
electric power tool (such as drill) is used in the proximity of the DDK-7. If this
occurs, plug the DDK-7 into an electrical outlet located as far as possible from
the device that seems to be the source of the problem.
This is caused by the proximity of a high-power broadcasting station, an
amateur ham radio setup or a mobile phone.
Because the DDK-7 is capable of producing powerful bass sounds,
resonance may be caused in surrounding objects, such as cabinets or glass
windows. To avoid this, relocate the objects or lower the DDK-7's volume.
Unfortunately, this is a common characteristic of TFT-LCDs.
• The Master Volume may be set around the minimum position. Turn it
clockwise.
• The Expression Pedal or Foot Pedal may not be pressed down. Press it
down with your toe.
"OFF" is selected in the Foot Pedal display. Select function to assign it to the
Foot Pedal. (page 203)
This happens very rarely. Occasionally, power surges and spikes due to
electrical storms or other reasons may cause the DDK-7 to malfunction and/or
alter the contents of memorized data. If this happens, perform the Factory Set
operation to reset the DDK-7 (page 24).
A cable of the Pedal Unit is disconnected. Make sure that power is OFF when
connecting or disconnecting the pedal.
The parts are assigned to AUX OUT SUB jacks. If you want to hear all parts
from Headphones, select AUX OUT MAIN jacks for all parts. (page 220) If you
want to hear all parts from an external speakers, use the output from the mixer.
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