Appendix
32
Troubleshooting.......................................................................

In many cases, problems or malfunctions that occur during use can be remedied easily.

Please check the following list before deciding that your DD-55 is damaged.

If the suggested remedy is ineffective, take the DD-55 to an authorized Yamaha dealer

for proper diagnosis and repair. Do not attempt to repair this digital instrument by

yourself as serious damage may occur.

Problem Cause/Solution
A buzz or click occurs momentarily when the
DD-55 is turned ON or OFF
This is a normal power surge noise that occurs when the
POWER switch is operated.
The LED display is completely dark. When the
pads are struck, the display is dark and returns
to “000”.
The batteries are low and should be replaced with a com-
plete set of six new batteries immediately. Ideally, an
optional AC adaptor PA-5C should be used to power the
DD-55 (see page 5).
The custom pad voice assignments have disap-
peared or defaulted.
No sound comes from the speakers. • The volume is set too low. Adjust the volume (see page 8).
• A plug is inserted into the PHONES/OUTPUT jack and
should be taken out (see page 7).
• The LOCAL ON/OFF is set to OFF. Set the LOCAL ON/
OFF to ON (see page 26).
• You are in the MIDI/Utility mode. Exit the MIDI/Utility
mode (see page 25).
Striking two pads simultaneously results in one
of the pads not sounding.
Refer to “Adjusting the Pad’s Sensitivity ” to resolve the
problem (see page 13).
Striking a pad results in other pads also sound-
ing, though they were not struck.
The selected voice does not sound when the
pad is struck.
The desired voice has not been assigned to the pad.
Use the PAD ASSIGN function to program the desired voice
to the appropriate pad (see page 11).
The song or Demo does not start playback. The MIDI clock has been set to “E” (external).
Change the MIDI clock setting to “I” (internal) (see page
25).
“C|r” appears in the display when the
POWER switch is turned ON, and backed up
data has been erased.
Backed up data is initialized if batteries are not installed or
AC adaptor is disconnected while the power is turned off
(see page 31).