Is there anyway to get Plex to use more available CPU power for background transcodes or have Plex do multiple background transcodes at once. Even with my background preset set to Ultra Fast, my Xeon E5-2680v3 barely hits 30% usage and my queue can take forever to finish.
No, background tasks only run 1 at a time. There isn’t a way to increase the performance since there isn’t a way to slow it back down should you need to transcode something live. If you need to convert a lot of files, it’s best to do it outside of Plex. If this is for Sync, you’ll just have to wait.