Firstly thank you to Avast for creating and maintaining one of the leading anti virus solutions.
I would like to know how to disable the “virus database has been updated” and other audio notifications.
Cheers.
Simply go to the program settings, switch to the Sounds page and check the option “Disable avast! sounds”.
Besides what Igor says (sounds disable), see ‘Settings’ on my signature.
Browse for SuppressUpdatedInfo value 
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