Adrian, go to the Sidebar Menu and then to the Settings Tab. Scroll down until you find "Video + Voice" section and under "Video/Player Avatar Size:" you can change the size of the portraits. NOTE: If you select "Names Only" while running Roll20 normally (not through Google Hangouts) you will not be able to use voice chat, because this deactivates TokBox. If you're in Google Hangouts, portrait size is usually automatically switched to "Names Only", but this doesn't affect the video/audio because Hangouts UI handles it.