Rate is not working for XiaoxiaoMultilingualNeural

[jackfengji]

The rate in prosody is not changing the real speaking rate for XiaoxiaoMultilingualNeural voice. It's not working in voice gallery web ui either.

This is the SSML I'm using. It's still very slow.

<speak xmlns="http://www.w3.org/2001/10/synthesis" xmlns:mstts="http://www.w3.org/2001/mstts" xmlns:emo="http://www.w3.org/2009/10/emotionml" version="1.0" xml:lang="zh-CN"><voice name="zh-CN-XiaoxiaoMultilingualNeural"><lang xml:lang="zh-CN"><s /></lang><mstts:express-as style="Default"><prosody rate="+200.00%">今天是我在新公司的第一天，入职后很快投入了新的工作环境并开始熟悉各项事务</prosody></mstts:express-as><s /></voice></speak>