Kurzweil SPS4-8 Musician's Manual page 108

Troubleshooting
Common Problems
If there's evidence of the unit receiving power, but operation is abnormal, check if one of
the following might be the issue:
12-2
The power adapter ratings does
not match the required ratings
for the SPS4. The power adapter
specifications are: 19V DC, 3.4
amp, center pin positive, 5.5mm
OD, 2.5mm ID coax type plug.
The wall outlet, power strip, or
extension cord is defective or
damaged.
The power adapter ratings does
not match the required ratings
for the SPS4. The power adapter
specifications are: 19V DC, 3.4
amp, center pin positive, 5.5mm
OD, 2.5mm ID coax type plug.
The wall outlet voltage is below
90 volts due to overload.
The power adapter plug does
not snugly fit into the DC power
jack, causing it to wobble and
provide intermittent power.
Obtain a compatible power adapter.
Use a different wall outlet, power
strip, or extension cord.
Obtain a compatible power adapter.
Try a different outlet on a different
circuit.
Obtain a compatible power adapter.