Hi,
Here are some troubleshooting steps that may help.
- First, do try to uninstall/reinstall the Realtek sound driver.
- Go to Device Manager and uninstall the Realtek sound card driver.
- Once uninstalled, download and install the latest driver from the manufacturers site.
- Reboot the laptop once the latest driver has been installed.
- After the reboot, do also make sure that Realtek is set to load upon boot.
- Open Task Manager and go to Startup tab and make sure that Realtek is enabled.