Roland GO:MIXER PRO-X Audio Mixer for Smartphones - Manual (Page 18)

(*6) If you want to record video using your camera app
or 4XCAMERA while playing back music from your
smartphone, turn the [LOOP BACK] switch “ON.”
(*7) Audio is output to the smartphone as two channels
(stereo).
(*8) If you are using the 4XCAMERA app, select some music
on your smartphone.
Tap 1 and then 2 to
select the music on your
smartphone.
2
1
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