@LucienMJ Apologies for any issues with the usage of words in the below example, I have used this only as a context to check if phoneme works with zh-TW as I am not a native speaker of chinese(taiwan)
I have used this an example to set phoneme for one of the words from the studio and it seems to work.
<phoneme alphabet="sapi" ph="ㄧㄚ">家</phoneme>
My SSML was set as the following:
<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-TW"><voice name="zh-TW-HsiaoChenNeural">客<phoneme alphabet="sapi" ph="ㄧㄚ">家</phoneme>語;</voice></speak>
Have you tried to use the studio and set the phoneme for zh-TW?
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