There are multiple things you can do if your Smart TV is freezing or stuttering:

1. Check if the device is connected to the Wi-Fi and if there is adequate signal strength.
   
2. Ensure that your set-top box or smart TV is up-to-date by checking for the latest firmware update.
3. Uninstall any apps on your Smart TV that could be causing the issue as some apps can become unstable over time.
4. Restart the device, either by powering off or unplugging it for a few minutes.
5. If available, reset the device to factory settings.