AudioSocket error — “Received AudioSocket message other than hangup or audio”

Asterisk Asterisk APIs
1

Hi everyone,

I’m working with Asterisk and the AudioSocket application to stream call audio to a Python server for processing (e.g., transcription).
However, during a live call, I’m seeing this error in the Asterisk logs:

[Oct 28 11:24:16] ERROR[136104][C-00000003]: res_audiosocket.c:295 ast_audiosocket_receive_frame_with_hangup: 
Received AudioSocket message other than hangup or audio, refer to protocol specification for valid message types
[Oct 28 11:24:16] WARNING[136104][C-00000003]: app_audiosocket.c:206 audiosocket_run: 
Failed to receive frame from AudioSocket server '127.0.0.1:4000' connected to channel 'PJSIP/tata-endpoint-00000002'

From what I understand, this means Asterisk received a message from my AudioSocket server that doesn’t match the expected binary audio format or hangup frame.

I’d appreciate help understanding:

  1. What exact message format Asterisk expects from the AudioSocket server (e.g., byte framing, headers, etc.).

  2. Whether I need to send any response back to Asterisk after receiving the audio frames.

  3. Any example implementation or reference Python code for a proper AudioSocket receiver that keeps the connection alive for the entire call.

Here’s how I’m starting the socket server (simplified):

server = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
server.bind(('127.0.0.1', 4000))
server.listen(1)
conn, addr = server.accept()
data = conn.recv(1024)
# process data...

What could be causing this protocol error, and what’s the correct way to handle or ignore messages so Asterisk doesn’t drop the stream?

Thanks in advance!