You need to be sure to allow Premiere plenty of time to complete
conforming all of the audio in your project before you try to edit.
If your project contains a lot of media files, this can take a lot
of time depending on your hardware setup.
If you interrupt the conforming and exit Premiere, the next
time you open the project, the conforming will continue.
I would delete all of the files in your Media Cache Files folder,
re-open the project, then wait patiently for conforming to finish.
Exit, wait a minute for all Adobe processes to close, then re-open.
If at that point you have a couple more media files conform... that's
not particularly unusual... let it finish, save / exit / wait / re-open.
If you are still re-conforming all audio files after this routine,
there might be a hardware or software configuration problem.
Many thanks, I'll give it a try!