When you encounter the sound quality problem while using the phone, please do the following troubleshooting:
1. Try to change the curve of the phone handles handset of both the calling caller and called parties and then test again.
2. Check if the connection between the phone handle handset and the curve of both the calling caller and called parties is normal.
3. The sound quality problem occurs during the call, immediately switch from the handle handset mode to the hands-free speaker mode or switch from the hands-free speaker mode to the handle mode handset mode to check whether there is a problem with the sound quality.
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