Hello there! I am Charity, I'm an Independent Advisor. I'm glad to help you today!
Launch Minecraft Bedrock Edition and keep it running.
Open the Volume Mixer:
Right-click the speaker icon in the system tray (bottom-right corner).
Select Open Volume Mixer.
Scroll through the applications list to see if Minecraft is listed. If not, Minecraft may not be routing sound correctly to the system.
We can also try to force Minecraft to use a specific output device.
Open Settings > System > Sound > Advanced sound options.
Under App volume and device preferences, find Minecraft and manually set the output device.
Kind Regards,
Charity
Please note that things might need more than one reply to completely resolve your issue, as it will completely depend on the complexity of the question and the amount of detail that you have provided me.