GR-55: PC TX (Program Change Transmit) Switch
If you want to transmit MIDI Program Change (PC) messages to an external device from the GR-55, its PC TX switch must be turned on.
1. Press EDIT.
2. Press the right or left PAGE button to select "SYSTEM," and then press ENTER.
3. Press the left or right cursor buttons to select "MIDI/USB," and then press ENTER.
4. Press PAGE left to select the GENERAL tab.
5. Use the up or down cursor buttons to select "PC TX SWITCH."
6. Turn the dial to select "ON."
7. Press EXIT twice when you're finished—the new setting is saved automatically.