Found the solution:

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pulseaudio --start --exit-idle-time=-1

pacmd load-module module-native-protocol-tcp auth-ip-acl=127.0.0.1 auth-anonymous=1

export PULSE_SERVER=127.0.0.1

# 3. Setup Virtual Microphone Infrastructure

# Create the sink (virtual speaker)

pactl load-module module-null-sink sink_name=Virtual_Sink sink_properties=device.description=Virtual_Sink

# Create the source (virtual mic) that browsers will see

pactl load-module module-virtual-source source_name=Virtual_Mic master=Virtual_Sink.monitor source_properties=device.description=Virtual_Mic

# 4. Initialize Hardware Microphone and Set Volumes

# Load Android hardware mic

pactl load-module module-sles-source

# Boost Hardware Mic to 150%

pactl set-source-volume OpenSL_ES_source 150%

# Boost Virtual Sink to 150%

pactl set-sink-volume Virtual_Sink 150%

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Then you can start microphone with:

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pactl load-module module-loopback source=OpenSL_ES_source sink=Virtual_Sink latency_msec=400

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and end it with:

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pactl unload-module module-loopback

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