Found the problem. Sound preference for input sound level needs to be set to Max-- Full-ON. Anything less can result in no sound at all.

I’ve done the install of both sunflower and soundcast on my iMac, which is running OS X 10.9.5. Test sounds work ok, but casting from QuickTime or iTunes results in nothing. Just empty air, no sound. The articles on this app make it sound so easy. It isn’t. I bought my Chromecast Audio this morning at 10am. It is now…