Wirecast has announced a "severe" issue causing connection issues with RTMP server urls. If you're experiencing this problem, we recommend switching to an alternate encoder until your receive the patch fix from Wirecast.
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Wirecast 10: Mojave Support
As you are most likely aware, macOS 10.14 Mojave is due to be released on Monday, September 24th. In macOS 10.14, we have discovered a severe issue causing a crash when streaming to destinations other than Facebook. We urge you to hold off on upgrading to 10.14 Mojave until we can release a fully compatible version. We expect to achieve full compatibility in version 11, slated for release the end October or beginning of November.
In the interim, we will be pushing out a 10.1.1 hot-fix for Mac users, to minimize issues as much as possible. This will be released as an in-app update notification, which will appear when you run Wirecast. We are aiming to release Wirecast 10.1.1 the same week of the Mojave release. This build will resolve the issues to most destinations...
Read the full article here:
http://telestream.force.com/kb/articles/Knowledge_Article/Wirecast-10-Mojave-Support
Alternative encoder (OBS):