Floob
Member
Post count: 1629

The global retroarch.cfg is at:
/opt/retropie/configs/all/retroarch.cfg

Check this section

# Audio volume. Volume is expressed in dB.
# 0 dB is normal volume. No gain will be applied.
# Gain can be controlled in runtime with input_volume_up/input_volume_down.
# audio_volume = 0.0