Hearing myself when using a Bluetooth headset

Dear AudioRelay Team,

I just reccently acquired the premium version of your app and for what concerns streaming audio from PC to phone, this app works absolutely perfect! However, when starting the AudioRelay Android App in server mode (exposing a bluetooth headsets microphone connected to the phone) I can hear the captured microphone audio looped back on the headset. At first I thought that I just selected the wrong audio sink on the desktop client. But the loopback already starts even before I connect to the server on the PC (before the linux desktop client is even started). It seems like the Android app itself causes the loopback for Bluetooth headset regardless if a Desktop client is yet connected or not.
My goal is to use my android phone as a remote bluetooth hub for a connected bluetooth headset (linux ble driver issue :frowning: ). The way I understand (please correct me if I am wrong) it this would require me to setup the phone both as a server (to send the microphone stream to the PC) and as a client (to receive audio output from the PC). But with this loopback behavior I mention above, the audio stream sent back to the phone is mixed with the captured microphone stream and thus barely understandable (and very low in volume).
Any help would be highly appreciated.

Could you please confirm that this behavior doesn’t happen in other apps?
What’s your phone’s model and Bluetooth headset?

Could it be due to the Sidetone feature? Hearing yourself would be normal then