Waveform issues on only 2 CDJs out of 20 I have played on

Hi there, 

Twice so far I have had a similar issue with the larger waveform and sometimes also hotcues not showing. This is causing some anxiety when I play new venues, as to what to expect.

The first time was using CDJ 900s, the second time was using CDJ 2000nxs.

The first time it happened, I thought I had made a mistake when syncing rekordbox with my USB. I also thought it could be that it could be that my USBs were corrupted. Thing is, both Sandisk Ultra USBs were bought at the same time and quite recently, and only ever used with Rekordbox. They are formatted correctly. And I triplechecked the contents of the USBs before ejecting properly.

Halfway through the set, I figured out that if I loaded a track, pressed BACK to the playlist, and reloaded the same track, the waveform would appear. This was helpful at least. 

The second time I experienced it, I had just bought a new SanDisk Ultra Flair USB (in case it was a USB issue). Loaded the USB and - same issue. Again, waveform appearing only after second or sometimes THIRD time loading a track. This time, no issues with hotcues showing. 

I should mention that it is not all tracks - it is mostly tracks which have been downloaded from a sharing platform. However, they are all good quality 320kbps MP3s, and it seems strange they work on all other controllers and CDJs I have used. It is also strange that a track would need to be loaded twice?

All help appreciated!