Notifly is a simple addon I have created for my wife that plays sounds when you get a whisper message from other players. We were using an UI addon for multiple years that had this functionality built-in, but with the new changes to the original World of Warcraft interface we had to find something new instead.
Every other addon is bloated with functionality, so that felt like an overkill. So here you go - Notifly is the addon you need for one and only one thing - playing a sound when you get a message.
Message to my wife: I love you 🥰.