I just upgraded and was playing a game that I record/instant replay often using ReLive. While in-game I used the SAVE INSTANT REPLAY hotkey and it saved a copy. When I opened the video it had no audio, other replays I have saved do not have this problem.
FX-8350
M5A97 LE R2.0
16GB DDR3
SAPPHIRE RX 580 4GB (STOCK SPEEDS)
19.1.1 - express install
So report it to AMD > Online Service Request | AMD
I already sent a report via the problem report wizard.
Maybe try the 'custom clean install' option ?
Did you look into your audio devices, maybe you can tweak there something? Changing default device or something.
I remember a few years ago I had not sound untill I delete "AMD high definition audio" from device manager.
I had this issue until I set Relive>Global>Audio Capture Device to Digital In (Sound Blaster Z) rather than "What U Hear"
Current settings are 96k for audio device (my max windows sound), 320kbps under Relive>Recording>Audio Bitrate
I would enable recording desktop and play music in the background and fiddle with the Audio Capture device until you find which setting works, that did it for me.