Hope all is well.
We use ADAU1361 in our design with two single ended microphones.
The two mics are connected to negative inputs as pseudo differential and grounded with AUDIO_GND.
When we unplug each microphone, we observe high background noise (not your typical noise floor).
We have the EVAL-ADAU1361, we do not observe the same using the same settings.
Below is the schematic;
We experimented with capacitor and resistor values but we were not able to find the cause of this floating noise.
Any help is much appreciated.