Audio drops out. Even happens occasionally with very fast SSD.

For reference, the files I edit are ProRes 3840x2160, 60fps, with 5.1 PCM audio. Approximarly 1 gigabit video bitrate, and 7 megabit audio bitrate. This should require approximately 129 megabytes per second of transfer speed. However, I do use a 30fps timeline, so it may require less overall. 

When I first started with a single 7200 RPM HDD, I could edit, but the audio would constantly drop out, leaving me with a muted picture, although I did have a lot of dropped frames. I worked around this by saving the audio to a different drive. 

Last year, I decided to stripe two 7200 RPM HDDs together, doubling the transfer speed. Overall, audio worked better, but there were still some areas where audio would drop out every time, requiring me to go back to the same process of keeping audio on a separate disk.

This year, I decided to get two 8TB SSDs (Samsung QVO) and stripe them together, achieving an effective transfer speed of about 1 gigabyte per second, or 8x what the video files should need. While audio drop out is indeed mostly gone, there are still occasional situations where the audio will cut out until I pause and resume playback. 

It really just seems very odd that even at 8x the required transfer speed, this still happens. Even the single HDD was technically above the transfer speed requirement, although only slightly. The lower frame rate time line should have given it more of a margin, but with HDDs, the seeking may still be similar regardless of frame rate. The 2x striped HDDs I thought gave plenty of margin above the transfer speed, but still wasn't good enough. While the 2x striped SSDs are good enough to work with 99% of the time, I am shocked to see this issue still happen occasionally. 

Honestly, despite transfer issues, audio playback itself requires a very slow transfer speed. You should be able to buffer a bunch ahead of time, or at least prefer that the video drop a frame rather than drop audio playback altogether. When these files can be played back on every other piece of software without issue, clearly there's something wrong in the Premiere pipeline that's causing this.