I have a few suggestions for you to try before you start working your way down the official troubleshooting list.  First, when in doubt try these three things: Reload the tab, restart the browser, reboot the machine.  This fixes some issues.  If that doesn't fix it, start down this checklist:  <a href="https://wiki.roll20.net/Audio_Visual_Troubleshooti" rel="nofollow">https://wiki.roll20.net/Audio_Visual_Troubleshooti</a>...      1 Make sure you’re using the most recent version of either Chrome or Firefox    2 Give Roll20 permission to use your microphone and camera    3 Make sure Video and Voice are turned on inside Roll20    4 Clear your Web Browser’s Cache    5 Make sure you have the right ports open    6 Check if your camera is working with WebRTC    7 Check that your camera is functioning    8 Do a bandwidth test    9 Solving Technical Issues    It is *very* important to use the right browser AND the right version of the browser.  You need to keep your browser up to date, but do NOT use unstable/nightly builds of Firefox.  If you're using NoScript and/or AdBlock, you have to allow *everything* the page tries to load.  Blocking just one element can bring the whole thing down.  Good luck!