@晓力 袁 Welcome to Microsoft Q&A Forum, Thank you for posting your query here!
I understand that you are encountering an error when calling the text-to-speech API in Microsoft Azure Cloud. The error message indicates
The request is throttled because you have exceeded the concurrent request limit allowed for your sub websocket error code: 4429.
The error code 4429 you’re encountering is related to exceeding the concurrent request limit for your subscription. The limits are explained in this article. If these limits are exceeded, your requests will be throttled.
Here are a few steps you can take to resolve this issue:
Check your subscription tier: Ensure that your subscription tier matches your usage needs. For instance, the standard tier (S0) allows for a higher number of transactions per second (TPS) compared to the free tier. If you are using free tier, You may need to consider to use the standard tier (S0) instead.
A standard tier TPS is 10 times higher than free tier. If you are already using standard tier and still seeing this error the limit, you might need to contact the support from Help+Support blade on azure portal and raise a case under service and subscription limits(quotas) and select your subscription and quota type as cognitive services and provide additional details about your resource and submit the request.
Upgrade your subscription: If you’re still on the free or student tier, consider upgrading to pay-as-you-go if you have exhausted your student credit limit.
Hope this helps.
If you have any further queries, please let me know. I would be happy to assist.
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