Fiio M17 - Page 11

-Play/Pause: Short press the Play/Pause button.
-Previous/Next track: Short press the Previous/Next track button.
SPDIF RX mode
When switching to the SPDIF RX mode, the system will automatically enable the coaxial port
as coaxial input mode. At this time, the M17 will start to decode the input valid coaxial
signals.