Open Discord on your PC
Click the User Settings gear icon
Select Notifications
Turn off Enable Desktop Notifications
Turn off Enable Taskbar Flashing if desired
Turn off Message Notification Sounds
Turn off Notification Sounds
Adjust server or channel notification settings if needed
Right-click a server or channel
Select Notification Settings
Choose Mute Server or Mute Channel
Set the mute duration if prompted
Close User Settings
Check your PC sound settings if Discord still makes sounds
Open Windows Sound settings
Lower Discord app volume or mute Discord entirely