Hello Wes,
There is a batch of units that have gone out into the wild where the audio fidelity is not optimal.
However, we have recently updated the circuity to the Mod Duo X and have fixed the audio issue that you have reported. We would like to get your unit to our facility so that we can apply the fix to your device. Could you please write to support@moddevices.com with the serial number of the Mod Duo X and with your shipping details.