Accuracy rate drop may due to various reasons, we have the following suggestions:

1. Click the voice button to end dictation when you finish your speech, wait 1-2 seconds for the auto-correction to finish.
   (Other button clicks to end dictation will lead to a lower accuracy rate.)
2. Speak closer to the microphone and use the speech-to-text function in a relatively quiet environment.
3. Use the software with your headset or external microphones.
4. Speak louder or increase microphone input level by following steps:
   Step 1: In Windows, go to > Settings > System > Sound.
   
   Step 2: Sound > Input > Device properties.
   
   Step 3: Increase the microphone input level.
   
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For more information, please see About Baidu Speech Input.