If the audio in your recordings is too low, although the computer audio-level and the knobs to increase audio volume on your audio mixer are in a 'normal' position (per default all knobs are centered), the active OUTPUT LEVEL might be wrong.
▪Make sure the OUTPUT LEVEL is set to MIC, to activate the pre-amplifier.
The little, white, square button next to the VDC power input selects the active INPUT LEVEL mode.
IMPORTANT: Not all devices show which position reflects what OUTPUT LEVEL mode, read the manual that came with the device, if it is not labeled on the device itself, because on some devices the functionality of this little white button is switched!