Roblox sound not working

Hi! My name is Pam. I'm an Independent Advisor and I'll be glad to help you today.

I'm sorry to hear that. It happened to me earlier and this is what I've tried.

Please Turn off console > (press and hold power button for 10 seconds) unplug everything from the console > wait for 2 minutes and plug everything back > Turn On the console.

If the issue still persist, This time, I'll be providing you a step to restore your console to its factory defaults to remove all potentially corrupted files that can interrupt you from using the console’s full potential. Nothing to worry as everything will stay intact, you just need to sign in using your account. No games or apps will be deleted. Make sure you know your emails and password, okay?

Press the Xbox button to open the guide.

Select Settings > System > Console info > reset then keep my games and apps.

It sounds more like a Roblox problem than something with Microsoft. Have you tried reaching out to the Roblox developer?

From what you've said, it sounds like you're doing the right steps. Here is some information on "Parents, Safety, and Moderation" for Roblox. There are several topics on how to help get your childs account working, and if none of those work you can select
Contact Us at the bottom of Roblox Support page. And of course we will continue to help you here in the Xbox Forums if their Support Page doesn't solve your issue.

Roblox "Parents, Safety, and Moderation" External Link

https://en.help.roblox.com/hc/en-us/categories/200213830-Parents-Safety-and-Moderation

Another good question to ask, while being an obvious one it is still something people overlook from time to time. Are you playing Roblox through the port of it on the Xbox One or are you trying to play it on PC through something like the Roblox website,
or in this case I believe the PC version of Roblox does have its own launcher akin to Minecraft. You'd need to be on the Xbox port of the game for achievements to work, I know that sounds like common sense but you'd be surprised how that can be a mistake sometimes.

What I meant by Roblox Developer is someone that works for Roblox and develops the Roblox game engine and platform not someone that makes games using the Roblox game engine.

Additionally try reaching out to roblox support.