Fiio M15S - In-Vehicle Mode Operation

Power-off timer
There are two types of the timer, Sleep and Idle poweroff.
Sleep
The device will automatically shut down when the time reaches the set value. It
can be set to any integer value between 0 and 120 minutes. (Note that if it is
turned OFF, the sleep shutdown function will be disabled.)
Idle poweroff
If the device is not working without any operation, it will automatically turn off
once the timer reaches the set value. It can be set to any integer value
between 0 and 50 minutes. (Note that if it is turned OFF, the idle shutdown
function will be disabled.)
Rotate screen
The display page will rotate 180° if it is enabled.
In-vehicle mode
【Principle】After turning on the In-vehicle mode, you can connect the USB 3.0
port of M15S to the on-board USB port. And the M15S will power on
automatically and switch to the In-vehicle mode screen when the vehicle
engine starts, and power off automatically when the vehicle engine stops.