Use the following steps to disable notification sounds in Windows 10.
1.) Open Control Panel.
2.) Select Hardware and Sound.
3.) Select Change system sounds link.
4.) Under "Windows", scroll and select Notifications.
5.) On the "Sounds" drop-down menu, select (None).
6.) Select Apply.
7.) Select OK.
Once you complete the steps you will continue to receive notifications and Action Center will work as before but you will not hear the same sound every time a new notification arrives.
To re-enable notification sounds use these same steps but for Step 5, select Windows Notify System Generic instead of (None).