Have you tried reanalyzing the tracks in question by right-clicking on them? I've had this issue when analyzing tracks on a network-drive with flaky WiFi but reanalyzing them fixed that for me.
Incomplete waveforms in Rekordbox and players too
This seems like exactly the same issue this user had , but I cant reply to the topic:
The track plays normally, but the waveforms are cut in the browser section and the deck. It happens the same on the CDJ/XDJ players themselves, the preview is broken halfway through, but the track plays normally and even the hot cues in the invisible part of the waveform are visible. Check out the attachment:
Im using Rekordbox 5.5.0 on a x64 Windows 7 machine
Yes, of course, that helps, but it's a pain that I have hundreds of them like this.
Where are your media files located? Are they on the harddrive on which your OS is running or are they on an external drive?
The same ssd.