The metronome function on the FantomS and FantomS88 are global system settings. To change the metronome sound or turn it on/off, Press MENU, the use the up/down buttons to select system, then press ENTER. In the System Setup section, select Metronome. There, you can change metronome settings, like the volume, what sound it uses, and whether it's on, off and when it plays (playback, record or both).

For more details, review the FantomS/FantomS88 Owners Manual, page 188, and page 192.