So I am using Adobe Premiere Pro 2018 with multicam sequences of UHD ProRES clips and separate 24 bit audio. And to see the waveform in Premiere the Audio needs to be rendered. The bug is that Premiere Pro loses this render each time I open Premiere, so I once again need to render the audio to see the waveform.
And this has been going on for a long time, as you can see from this post at the Adobe Forums, they were going to fix this ASAP as of February 2017, but is July 2018, and the bug still persists.
I have also posted about it on the new feature and bug request page.