It seems like you are facing an issue with audio not playing from another tab or WhatsApp on the sidebar. This could be related to browser settings or restrictions. You can try the following:

Check Browser Permissions: Ensure that the browser allows audio from other tabs.
Disable Muting: Some browsers mute background tabs by default. Check if the audio is muted.
Refresh/Restart: Sometimes refreshing the page or restarting the browser can solve the issue.
Update Browser: Make sure your browser is up to date to avoid compatibility issues.
Check WhatsApp Settings: Ensure that sound notifications for WhatsApp are not disabled.