RuarkAudio R2 mk4 Manuel De L'utilisateur page 17

Line in
Listen to an external audio device using a 3.5mm
stereo jack cable connected to the Line in socket on
the back of your R2.
Input level
MENU > Input level
Adjust the input level and choose the highest level
that does not distort - if it distorts, turn down the
input level.
1 - Devices with high output level, eg some CD players
2 - Most devices
3 - Devices with low output, eg some smartphones
4 - Devices with a very low output
If your external audio source has a volume control
you may need to adjust it for best performance. If
it's too high the sound may distort; if it's too low the
playback volume may be too low and lack bass.
USB
Your R2 plays MP3 audio tracks stored on a USB C
flash drive. Plug it into the USB socket on the back
and change the source to USB.
Select Track list to view the tracks stored on your
flash drive and select one to start playback.
Press to skip to the next track in the folder or
album, press to skip to the start of the current
track, press again to skip to the previous track.
Press to pause playback or restart a track.
Press and hold or
rewind a track.
If a USB flash drive is not detected, it will show
"No USB device found".
Your USB flash drive must be formatted as FAT32.
NTFS, exFAT, or other formats are not supported.
Your R2 has a 5W, 1.0A USB power output and will
charge most devices but it may not charge devices
that require more than 5W.
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