fix(twilio): add configurable startup delay to avoid initial audio jitter (fixes #1906)

[Shraman123]

Fixes #1906

This PR reduces a short audio "jitter"/skip at the start of the Twilio realtime voice example by adding a small, configurable startup delay (env: TWILIO_STARTUP_DELAY_S, default 0.5s) before the realtime session, Twilio message loop and buffer flush tasks are started. This allows the websocket and audio buffers to settle and prevents missing the first audio frames.

Change summary:

• Add configurable startup delay (TWILIO_STARTUP_DELAY_S) in examples/realtime/twilio/twilio_handler.py
• Default value: 0.5 seconds

Manual check:

• Verified locally with a Twilio test call + ngrok (0.5s eliminated initial pop). If preferred by maintainers, I can replace this with a deterministic startup-buffer approach (buffer first N chunks then flush) — happy to implement either.

Thanks!

[seratch]

Thanks for sending this pull request! I think we can have this change for now, but if you're fine to work on the following quickly,

If preferred by maintainers, I can replace this with a deterministic startup-buffer approach (buffer first N chunks then flush)

this is definitely the best approach for us. Let me know if you're willing to take more time for this. Otherwise, we can merge this PR as an immediate workaround.

[Shraman123]

Thanks for the feedback @seratch! 🙏

I’ve updated this PR to switch from a time-based delay to a deterministic startup warm-up:

• Buffer the first N chunks of incoming Twilio audio (env TWILIO_STARTUP_BUFFER_CHUNKS, default 3 × 50ms).
• Once the threshold is reached, flush buffered audio to OpenAI and mark warmed; subsequent audio is sent immediately.
• Kept TWILIO_STARTUP_DELAY_S as optional knob, but default is now 0.0 since buffering is preferred.

Happy to tweak defaults, naming, or placement if you prefer this logic elsewhere. 👍

[seratch]

Can you resolve the lint error?

[Shraman123]

Fixed the lint issues and rebased on the latest main all clean now ✅

[Shraman123]

Hi @seratch 👋
I've fixed the formatting and verified everything locally.
All checks should pass once the workflow is approved ✅
Please review again when you get a chance — thanks!