从http://yuyin.baidu.com/docs/asr/58页面里下载的示例音频文件，识别时报3301
➜ cat test.py
# -*- coding: utf-8 -*-
from aip import AipSpeech

client = AipSpeech('xxxxx','xxxxxxx','xxxxxx')
print client.asr(speech='~/Downloads/aip-python-sdk-2.2.0/16k.pcm', format='pcm', rate=16000, options=None)
➜ python test.py
{u'err_no': 3301, u'err_msg': u'speech quality error.', u'sn': u'69030424441527489751'}