The following is troubleshooting information if you're not able to hear synth sounds coming from the GR-55's outputs:
- Make sure that you are connected to your amp (or mixer/PA) using the L/MONO and/or R OUTPUT - not the GUITAR OUTPUT. (The GUITAR OUTPUT will only produce your "dry" or unprocessed guitar sound).
- Make sure that your sensitivity settings have been adjusted accordingly.
Refer to "Adjusting the Input Sensitivity (GK SENS) in the GR-55 manual. - Make sure your GK pickup 3-position switch is set to "MIX" or "SYNTH."
- Check the GK 13 pin cable. Confirm that it is properly connected at both ends.
- Is your amplifier or mixer's volume turned up?
Try connecting headphones into the PHONES output jack on the GR-55. - Confirm that the VOLUME/EXP PEDAL is in a "toe-forward" position on the GR-55.
For most patches, it is controlling the master volume level. - Make sure the OUTPUT LEVEL knob is up on the GR-55 as well as the GK Volume knob on the pickup.
Lastly, try a Factory Reset and see if that helps: GR-55: Factory Reset (Initialize)
Caution: All User information is lost during a Factory Reset. Be sure to first back up anything you wish to keep before proceeding.