How can I know when an agent and customer start talking in a Callback using Eventbridge notifications?

Hello.

I need to trigger a backend service whenever an agent starts interacting with a customer in voice interactions. I've been successful with inbound voice interactions, using the Eventbridge metrics notification topic. I listen to when the tAnswered and tTalkComplete metrics are emitted, and it has worked so far.

But it doesn't work with callback outbound interactions. How can I capture this moment when customer and agent start talking to each other in callbacks?

Appreciate the help.

Hello.

Bumping this post. Please any help would be appreciated.