AWS Real-time Transcribe delays on Debian 12 (works fine on macOS)

[suyong21]

I’m using AWS real-time STT (amazon-transcribe) with
stream = await client.start_stream_transcription(...)

On macOS, everything works fine.
But on Debian 12, I’m seeing unexpected delays.

Symptoms

• Running start_stream_transcription alone works fine.

• However, when I also use in the same process:
  boto3.client (for AWS TTS),
  spaCy (for sentence segmentation),
  then all tasks (STT results, boto3 calls, spaCy processing) experience noticeable delays.

• It looks like something in Debian 12 causes the whole event loop or async tasks to slow down.

Environment

• OS: Debian 12
• Python: 3.12.3
• boto3: 1.40.34
• amazon-transcribe: 0.6.4
• spaCy: 3.8.7

Question

• Has anyone experienced similar latency or performance issues with AWS real-time Transcribe on Debian 12?-
• Since it runs fine on macOS with the same code, what could be different on Debian 12 that causes these delays?-