Cause of intermittent 'BadRequest' error in Send Multiple Events action for Azure Event Hubs

Question

I use the Send Multiple Events built-in connector action in a Azure Logic Apps Standard stateful workflow and I've recently started getting random 'BadRequest' errors. The action is not automatically retried in such a situation, but having implemented an explicit routine to attempt delivery several times, the request will ultimately go through to the Event Hub.

This is the more detailed error I get:

{
    "statusCode": "BadRequest",
    "body": {
        "code": "ServiceProviderActionFailed",
        "message": "The service provider action failed with error code 'BadRequest' and error message 'No such host is known.'."
    }
}

What could be root cause for such an error?