Standard image previews appear distorted

[Squiffer]

On my most recent import, the first of Lightroom Classic CC, some of the standard image previews appear distorted - as in the screenshot below. 1:1 and smart previews don't have this issue.

I've tried disabling GPU support which had no effect. Also tried deleting the previews data file and rebuilt the previews which also had no effect.

If I create a 1:1 or smart preview for one of the affected images, then immediately discard that preview, the remaining standard preview displays correctly!

Has anyone encountered this before?

Thanks in advance!

Lightroom version: Classic CC 7.4

OS: macOS 10.13.5

Hardware: 2017 MacBook Pro

[dj_paige]

There is some corruption of the files. This is caused by a hardware malfunction somewhere. The hard disk might be failing, so I would run diagnostics on it. Other possible causes of corruption are memory, and the hardware used to transfer the photos from camera to computer.

[Squiffer]

Thanks for your reply dj_paige

If the affected photos are opened in the Develop tab they load perfectly fine, they also load fine in other software such as Photoshop and Preview.

Could the files still be corrupt in this case?

[dj_paige]

Yes, your previews are corrupt somehow, but apparently not your actual photos.