Muting a chat is easy, here is a simple guide ...
Log into your WAX account using your email and password.
Go into your messages by clicking the second bottom right messaging icon.
Find the group chat you would like to Unmute and swipe left.
This will give you the option to Unmute or Leave the chat.
Click on Unmute.
This will immediately Unmute the chat, if it gets too noisy again, simply left swipe again, and press Mute.