If using the ZED-10 / ZED-10FX to record via USB and the signal strength into the recording software appears too low, the gain structure between the mixer, soundcard and software may need to be adjusted.

There are 3 ways of routing audio to the USB soundcard, either using the Record Bus, the Aux-FX bus or the Main L-R Bus, to select which, you will need to assign the USB OUT Source selector switches.
 
If recording using the Record bus, check the signal strength on the channel is OK by monitoring the Channel Input levels, to do this, enable Listen on the channel you are recording to monitor the Input signal on the L-R meters.
Adjust the channel Input Gain so the signal reads around 0dB on the meters, making sure the signal is not too hot so as to leave headroom for any potential peaks during the performance.  With the Input Gain set and the Record switch enabled, if you then adjust the Channel Level this will send the audio signal onto the record bus and into the recording software via USB.

With the recording software configured to use the USB Audio Codec as its sound device, the levels can now be set.
Most recording software will have the ability to monitor the incoming signal from the soundcard inputs, if the software has an Input Trim ensure this is not attenuating the signal, then adjust the ZED Channel Level to set the desired signal level on the meters within the software, with up to +10dB gain on the ZED Channel Level pot, there should be enough headroom to achieve a good signal into the software.
Once the optimum level is set you are ready to record.

If the level into the software still appears to be low, check the volume settings in the operating systems sound device settings is not down.
If the soundcard volume settings are up, the signal on the Channel Input is good and the ZED Channels Level is up there shouldn't be any problems adjusting the levels as required.

If recording the FX-Aux bus, set the Input Gains as above, then adjust either the FX or the Aux pot on the channel you want to record to send the audio signal to the Aux-FX bus and into the recording software via USB.
If sending the signal using the Aux pot, this will send the signal to the Left soundcard channel in the software, the signal level will not be affected by the ZED Channel Level control but it will be affected by the Aux Mix level so if the signal’s too low on the meters in the software, try adjusting the Aux Mix level.

If sending the signal using the FX pot, this will send the signal to the Right soundcard channel in the software, the signal level will be affected by the ZED Channel Level control so if the signal is too low, try adjusting the Channel Level.

If recording multiple channels on the main L-R bus, set the Input Gains as above, then adjust each channel Level so the combination of all the channels sits together nicely in the mix, this will then send the audio signal onto the Main L-R bus and into the recording software via USB.
It may help to apply some panning on the channels to separate the audio for a better stereo representation in the recording.
If the signal is too low in the recording software you will need to adjust the Main L-R Level to boost the signal.

If you have tried setting the gain structure as above and are still experiencing difficulties getting a good level of signal into the software, please contact your dealer or local A&H distributor for further assistance.