src/Broadcast/Broadcast.php
public function sendVoice($message, $to = null)
    {
        return $this->send(self::MSG_TYPE_VOICE, $message, $to);
    }
public function sendVoice($message, $to = null)
    {
        return $this->send(self::MSG_TYPE_VOICE, $message, $to);
    }
public function sendVoice ( $ message , $ to = null ) { return $ this -> send ( self :: MSG_TYPE_VOICE , $ message , $ to ) ; }
Send a voice message.

@param mixed $message message
@param mixed $to

@return mixed
Send a voice message .