AudioClip.isReadyToPlay
var isReadyToPlay: bool;
bool isReadyToPlay;
isReadyToPlay as bool
Description

Is a streamed audio clip ready to play? (Read Only)

If the AudioClip is downloading from a web site, this returns if enough data has been downloaded so playback should be able to start without interruptions. For AudioClips not associated with a web stream, this value always returns true.
	function Start () {
		var www : WWW = new WWW("www.example.com");
		audio.clip = www.audioClip;
	}

function Update () { if(!audio.isPlaying && audio.clip.isReadyToPlay) audio.Play(); }
using UnityEngine;
using System.Collections;

public class Example : MonoBehaviour {
    void Start() {
        WWW www = new WWW("www.example.com");
        audio.clip = www.audioClip;
    }
    void Update() {
        if (!audio.isPlaying && audio.clip.isReadyToPlay)
            audio.Play();
        
    }
}
import UnityEngine
import System.Collections

public class Example(MonoBehaviour):

	def Start() as void:
		www as WWW = WWW('www.example.com')
		audio.clip = www.audioClip

	def Update() as void:
		if (not audio.isPlaying) and audio.clip.isReadyToPlay:
			audio.Play()