You can control individual volumes. I think you click or right click on the "volume" icon near their token on the left side of the screen?The voice chat is just terrible. It's very low quality and there's no way of controlling individual volumes so you get some people you can barely hear and others who are booming in your ear.
Also, I am assuming that the map tile and PC/monster token selections are limited because it's the beta.
One fairly foolish design decision regarding the icons is that they are each a set size. If you give a Medium monster a Large icon, it will be large on the map. Some automatic scaling would be nice, and would open up image re-use. For example, having a "black dragon" token that could be used to represent a black dragon of any size category.