This error is caused by the TTS service's rate limiting, typically due to too many concurrent requests or insufficient pause between requests.
Solution:
- Go to the software's menu: Tools -> Advanced Options -> TTS Settings.
- Set "Concurrent TTS Threads" to
1. - Set "Pause After TTS (seconds)" to a value between
5 and 10 seconds. - Save the settings and restart the software.
This adjustment reduces the request frequency to comply with the service's limits, especially for free services like Edge-TTS.
Please refer to the related documentation: