# Conversation agent suddenly starts talking in gibberish **URL:** \ **Category:** Support Help\ **Tags:** agent-performance\ **Created:** [April 14, 2026, 3:55pm UTC](https://community.retellai.com/t/conversation-agent-suddenly-starts-talking-in-gibberish/2338 "2026-04-14T15:55:10Z")\ **Posts on this page:** 14\ **Page:** 1
**Author:** ![sabari.selvaraj](https://yyz2.discourse-cdn.com/flex008/user_avatar/community.retellai.com/sabari.selvaraj/32/1523_2.png) [@sabari.selvaraj](https://community.retellai.com/u/sabari.selvaraj)\ **Post date:** [April 14, 2026, 3:55pm UTC](https://community.retellai.com/t/conversation-agent-suddenly-starts-talking-in-gibberish/2338/1 "2026-04-14T15:55:10Z")
We are currently facing an issue with the retell voice agent conversation flow where the agent suddenly starts talking in gibberish for no reason. Are you guys aware of this issue and what is the recommended solution to fix this? Please help Agent ID: agent\_63dabd5bf547ebda9c1ef1f409 Workspace ID org\_zi03os7DAPhVwPYj ---
**Author:** ![mark1](https://yyz2.discourse-cdn.com/flex008/user_avatar/community.retellai.com/mark1/32/2524_2.png) [@mark1](https://community.retellai.com/u/mark1)\ **Post date:** [April 14, 2026, 3:59pm UTC](https://community.retellai.com/t/conversation-agent-suddenly-starts-talking-in-gibberish/2338/2 "2026-04-14T15:59:08Z")
Hello @sabari.selvaraj Can you share some Call Ids? Where you faced that issue. Thank You ---
**Author:** ![sabari.selvaraj](https://yyz2.discourse-cdn.com/flex008/user_avatar/community.retellai.com/sabari.selvaraj/32/1523_2.png) [@sabari.selvaraj](https://community.retellai.com/u/sabari.selvaraj)\ **Post date:** [April 14, 2026, 7:35pm UTC](https://community.retellai.com/t/conversation-agent-suddenly-starts-talking-in-gibberish/2338/3 "2026-04-14T19:35:28Z")
Sure! Please check this from 5:40 call\_4cddf9f61e95a57b7c404f1d8c7 ---
**Author:** ![mark1](https://yyz2.discourse-cdn.com/flex008/user_avatar/community.retellai.com/mark1/32/2524_2.png) [@mark1](https://community.retellai.com/u/mark1)\ **Post date:** [April 14, 2026, 7:37pm UTC](https://community.retellai.com/t/conversation-agent-suddenly-starts-talking-in-gibberish/2338/4 "2026-04-14T19:37:20Z")
Hello @sabari.selvaraj Thank you for sharing Call ID. I’ve forwarded them to our team for review, and we’ll get back to you as soon as we have an update. Thank you for your patience! ---
**Author:** ![mark1](https://yyz2.discourse-cdn.com/flex008/user_avatar/community.retellai.com/mark1/32/2524_2.png) [@mark1](https://community.retellai.com/u/mark1)\ **Post date:** [April 14, 2026, 8:00pm UTC](https://community.retellai.com/t/conversation-agent-suddenly-starts-talking-in-gibberish/2338/5 "2026-04-14T20:00:17Z")
Hello @sabari.selvaraj It looks like this may have been a transient issue with our voice service during that call. If you’re still experiencing this on more recent calls, please share those call IDs and we’ll be happy to investigate further. Thank you! ---
**Author:** ![anthonyg](https://yyz2.discourse-cdn.com/flex008/user_avatar/community.retellai.com/anthonyg/32/1542_2.png) [@anthonyg](https://community.retellai.com/u/anthonyg)\ **Post date:** [April 15, 2026, 5:49am UTC](https://community.retellai.com/t/conversation-agent-suddenly-starts-talking-in-gibberish/2338/6 "2026-04-15T05:49:09Z")
I’ve getting the same issue. It is happening on calls with GPT 5.4 nano, claude sonet 4.5, claude opus 4.6. I haven’t tried other models but it seems to be a voice issue rather than an LLM issue. ---
**Author:** ![mark1](https://yyz2.discourse-cdn.com/flex008/user_avatar/community.retellai.com/mark1/32/2524_2.png) [@mark1](https://community.retellai.com/u/mark1)\ **Post date:** [April 15, 2026, 1:09pm UTC](https://community.retellai.com/t/conversation-agent-suddenly-starts-talking-in-gibberish/2338/7 "2026-04-15T13:09:11Z")
Hello @anthonyg Please share those recent call IDs where you faced that issues. Thank You ---
**Author:** ![fabricio](https://yyz2.discourse-cdn.com/flex008/user_avatar/community.retellai.com/fabricio/32/851_2.png) [@fabricio](https://community.retellai.com/u/fabricio)\ **Post date:** [April 16, 2026, 2:03am UTC](https://community.retellai.com/t/conversation-agent-suddenly-starts-talking-in-gibberish/2338/8 "2026-04-16T02:03:47Z")
I’m also seeing this issue really often with my agents! Sounds super creepy Here are the examples just from today, just a few of many… EX 1: (0:20 sec. mark) Agent ID: agent\_e61005d60481ef4b93dbc8b998 Call ID: call\_ab5d835e283d119a7e290690553 > **[RETELL GLITCH 1](https://drive.google.com/file/d/1uBanCBhwOVahWFfU3Mf3Pb2jE1DtK3xp/view?usp=sharing)** > > Google Drive file. EX 2: (3:15 mark) Agent ID: agent\_e61005d60481ef4b93dbc8b998 Call ID: call\_96a3ce5acc30c5642b8ab64162b > **[RETELL GLITCH 2 (3:15)](https://drive.google.com/file/d/1WTV2allIw0x6uIFeW_yAE_lRojpLeTYK/view?usp=sharing)** > > Google Drive file. ---
**Author:** ![sabari.selvaraj](https://yyz2.discourse-cdn.com/flex008/user_avatar/community.retellai.com/sabari.selvaraj/32/1523_2.png) [@sabari.selvaraj](https://community.retellai.com/u/sabari.selvaraj)\ **Post date:** [April 16, 2026, 9:20am UTC](https://community.retellai.com/t/conversation-agent-suddenly-starts-talking-in-gibberish/2338/9 "2026-04-16T09:20:33Z")
We are still facing the issue where the agent suddenly starts talking in gibberish. Here are the details. We are really annoyed by this issue. Please resolve it soon. agent\_4ba453dd84c59c28e5770a0dc5 call\_530a4b9fb6aca7884c54033fcfa org\_zi03os7DAPhVwPYj ---
**Author:** ![mark1](https://yyz2.discourse-cdn.com/flex008/user_avatar/community.retellai.com/mark1/32/2524_2.png) [@mark1](https://community.retellai.com/u/mark1)\ **Post date:** [April 16, 2026, 2:55pm UTC](https://community.retellai.com/t/conversation-agent-suddenly-starts-talking-in-gibberish/2338/10 "2026-04-16T14:55:47Z")
Hello @sabari.selvaraj I’ve followed up with our team again and notified them to take another look. We’ll keep you updated as soon as we have more information. Best regards ---
**Author:** ![mark1](https://yyz2.discourse-cdn.com/flex008/user_avatar/community.retellai.com/mark1/32/2524_2.png) [@mark1](https://community.retellai.com/u/mark1)\ **Post date:** [April 16, 2026, 4:24pm UTC](https://community.retellai.com/t/conversation-agent-suddenly-starts-talking-in-gibberish/2338/11 "2026-04-16T16:24:08Z")
Hello @sabari.selvaraj Have you deleted the agent? ---
**Author:** ![sabari.selvaraj](https://yyz2.discourse-cdn.com/flex008/user_avatar/community.retellai.com/sabari.selvaraj/32/1523_2.png) [@sabari.selvaraj](https://community.retellai.com/u/sabari.selvaraj)\ **Post date:** [April 21, 2026, 5:22am UTC](https://community.retellai.com/t/conversation-agent-suddenly-starts-talking-in-gibberish/2338/12 "2026-04-21T05:22:25Z")
Hello Mark1, I believe my team might have done that. Any change you can still diagnose the issue for us? Because, the current system also has this issue ---
**Author:** ![sabari.selvaraj](https://yyz2.discourse-cdn.com/flex008/user_avatar/community.retellai.com/sabari.selvaraj/32/1523_2.png) [@sabari.selvaraj](https://community.retellai.com/u/sabari.selvaraj)\ **Post date:** [April 21, 2026, 6:08am UTC](https://community.retellai.com/t/conversation-agent-suddenly-starts-talking-in-gibberish/2338/13 "2026-04-21T06:08:14Z")
Please check this agent and call recording for the gibberish issue. We will ensure this agent is not deleted for now. agent\_13077c7ee7b3c54949934699ee call\_8c496e5414f3dad9066640c025d ---
**Author:** ![mark1](https://yyz2.discourse-cdn.com/flex008/user_avatar/community.retellai.com/mark1/32/2524_2.png) [@mark1](https://community.retellai.com/u/mark1)\ **Post date:** [April 21, 2026, 6:35pm UTC](https://community.retellai.com/t/conversation-agent-suddenly-starts-talking-in-gibberish/2338/14 "2026-04-21T18:35:09Z")
Hey @sabari.selvaraj The issue is in your conversation flow’s New\_Patient\_Collect node. The prompt uses bracket notation `[read callingNumber as XXX-XXX-XXXX]` as a formatting hint for the AI. When the caller had no caller ID (anonymous), the phone number variable was empty, but the model still attempted to follow the confirmation path and spoke the bracket text literally — which is what produced the gibberish. Here’s how to fix it: - Replace the bracket notation with explicit natural-language instructions, e.g.: _“Read the caller’s number back to them one digit at a time in the format XXX-XXX-XXXX.”_ - Add a hard guard for anonymous callers: make the prompt explicitly check if callingNumber is empty _before_ offering to confirm digits, and skip straight to asking for their number manually if so. - Optionally, use Retell’s `{{variable}}` syntax for dynamic values instead of relying on the LLM to interpret bracket directives. This is a prompt design issue — no platform bug. The TTS, LLM, and telephony layers all worked correctly; the model just output the formatting instruction as spoken text instead of interpreting it. Thank You