This difference is caused by different dB values used in digital and analogue domains and in DAW recording programs.
Qu is operating at -18dBFS in the digital domain. This is normal and allows for headroom in the conversion stage to avoid clipping / digital distortion.
0dB on our metering equals +4dBu on an analogue output.
DAW meters usually show values in dBFS (Full Scale) where 0 dBFS means the maximum value which can not be exceeded.
So if the meters on the Qu show 0dB this will equate to approximately -18dBFS in your DAW.
Here is another explanation: http://www.record-producer.com/what-is-the-difference-between-0-db-and-0-dbfs#.VO2jLfmsV8E
If you require a higher level when recording, it is best to normalise or boost the audio later using a DAW or audio editor as boosting this level beforehand will not provide you with any extra data.
You will simply be reducing your dynamic range, increasing noise and losing the safety-net of the headroom.
Note that this is not the same as with an analogue console, where to achieve the best quality you often want keep levels at around 0dB on meters throughout the system.
For live streaming / broadcast where it is not possible to adjust levels later, check if the program has an input trim, or make use of up to +18dB make-up gain in the compressor on your mix output channel to 'trade' -18dB headroom for +18dB output level.