The main reason you may not hear the audible signal in the TRS is due to your browser settings. Please make sure that the browser settings are configured to allow for the notifications.

For Firefox: 

1. Click the hamburger icon and click Options 
2. Then click Privacy & Security 
3. Click on Permissions 
4. Then select Autoplay Settings 
5. Finally, select Allow Audio & Video and save the changes

For Safari: 

1. Launch the workstation
2. Right click the address bar and select 'Settings for This Website'
3. Locate the dropdown menu 'Auto-play' and select 'Allow All Auto-Play' 

For Chrome: 

1. Find the 3 dots in the top right corner and click on them
2. Then click Settings
3.  Select Privacy & Security
4.  Find and click Site Settings 
5. Look for content settings and click Additional Content Settings 
6. Finally select Sound and allow sites to play sound