Hi Simon-Pierre Tessier,
Greetings & Welcome to the Microsoft Q&A forum! Thank you for sharing your query.
I'm sorry to hear that experiencing issues with the Emma voice in Azure TTS.
Regarding the discrepancy between US East1 and US East 2, it’s possible that differences in the underlying infrastructure or software across regions may be impacting the performance or behavior of the Emma voice in US East 1.
To address this issue effectively, we recommend raising a support ticket with Azure. Please include detailed examples, such as audio samples highlighting the discrepancies, and specify that the problem is isolated to US East 1. This will help the Azure support team investigate and resolve the issue promptly.
Hope this helps. Do let us know if you have any further queries.
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