Eliminate Re-Conforming Files
Premiere Pro constantly performs and redoes "conforming" of files each time a project is opened. The same files are redone each time.
This seems to happen most often with MP3 files.
Rather than re-doing the same work on the same files each time, Premiere should save these conforms so they can be referred to rather than redone.
Normally, each file is conformed only once, and conform files persist across sessions.
Is the media perhaps on a file server, whose clock is not synchronized to the edit system? That’s one common cause of reconforming.
R S commented
The media is stored locally on a LaCie RAID (USB and/or Thunderbolt).
If the conforms were exposed to the user in a meaningful way, they could be checked / linked in a way similar to proxies.