As of August 12th, 2019, our engineering team isolated an issue that's causing audio capture from Google Chrome during screenshare to fail for some users.
This was due to some changes in Chrome's audio infrastructure, and our team is working quickly to accommodate Google's updates to make sure screenshare works as expected! Our team has released a handful of initial patches to address this issue and will continue to work on the screenshare code over the next few patch releases, so please make sure to update to the latest version of Discord as a first step if you're still having trouble!
As a next step, if you're still having issues capturing audio from Google Chrome as of our latest update, make sure to try the following workaround!:
1) End your screenshare session and refresh the app with Ctrl + R
2) Close Google Chrome then reopen it. Once Chrome is reopened, begin playing audio in the browser before launching a screenshare session.
3) Enable screenshare and try once more!
If you're still having trouble after giving this a shot, our support team is collecting data so we can get this fixed for everyone as soon as possible, so please don't hesitate to reach out to the team directly here!