@Paul McGurn Welcome to Microsoft Q&A Forum.
Thanks for your valuable feedback. We appreciate your inputs and pointers in improvising our products and services.
For the Feature requests
feedback, I would suggest you to raise this request in our Azure feedback forum mentioned below:
https://feedback.azure.com/d365community/forum/09041fae-0b25-ec11-b6e6-000d3a4f0858
The Speech Service Product owners have the direct visibility on to this and they can share the updates on roadmaps etc.
Hope this helps.
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