Thanks — I’m responding about the error message: "twirp error unknown: max auth retry attempts reached for SIP invite." What it means: • An inbound SIP INVITE failed because LiveKit retried SIP authentication the maximum number of times and all attempts failed. • This happens during SIP trunk authentication when LiveKit cannot verify the caller/provider credentials. Likely causes: • Incorrect

auth_username

or

auth_password

in your SIP trunk configuration. • Trailing whitespace or unexpected characters in credentials. • Mismatched credentials on the SIP provider side. • Network issues causing repeated auth failures. • The SIP provider/trunk not being active or reachable. Suggested troubleshooting steps: 1. Verify

auth_username

and

auth_password

exactly match the values from your SIP carrier (no extra spaces). 2. Check the SIP trunk status on the provider side to confirm it’s active and accepting auth requests. 3. Inspect LiveKit and SIP provider logs for earlier authentication failure messages (they often show the cause of each retry). 4. Test connectivity (SIP/TCP/UDP ports) between LiveKit and the SIP provider to rule out network drops. 5. If you recently rotated credentials, update them in LiveKit and retry the call. If you’d like, share: • which SIP trunk settings you’re using (redact secrets), • a short snippet of the auth config or log lines around the failure, and I’ll help pinpoint the cause. Sources: Preserving Caller ID During SIP Transfers in LiveKit Agents | Layered Caller Verification for LiveKit SIP Calls | LiveKit, with interactive elements