I have this really annoying bug regarding recording with Relive. It was happening on 17.8.1 and now it's happening on 17.8.2 and has been like it since driver install. Basically what happens is, when I go into the Relive recording options, if I only have the AVC encoding option available, trying to record any gameplay or desktop simply doesn't work. I can hit ALT+Z to bring up the panel, I can take screenshots with CTRL+SHIFT+E but when I try recording, the small little recording timer pops up in the corner of the screen and disappears straight away. Now, I have recorded but only when the HEVC option was available. I have removed drivers, used DDU and AMDCleaner multiple times, but once the driver is installed and I chose the HEVC option for recording, after I record the first time, the HEVC option disappears and I then can't record anything when its on AVC.
I've a friend that has the exact same issue.