Lightroom Classic 15.5.1 - Develop module very slow when moving between images

Lightroom Classic 15.5.1 - Develop module very slow when moving between images

Lightroom Classic has become noticeably slow when moving from one image to the next in the Develop module.

When I press the left/right arrow key to move to another RAW image, the new photograph appears, but the Develop controls, including the Basic panel, remain greyed out and unavailable for several seconds before becoming active.

This makes editing large wedding galleries extremely slow, as the delay occurs repeatedly when moving through images.

System:
Windows 11
NVIDIA RTX 3070 Ti 8GB
32GB RAM
Nikon D780 NEF files
Lightroom Classic 15.5.1
Camera Raw 18.5.1

Troubleshooting already tested:

• Happens with a collection containing hundreds of photographs
• Also happens with a folder containing only 12 photographs
• Built Smart Previews and enabled "Use Smart Previews instead of Originals for image editing" - no improvement
• Disabled Smart Preview editing and used original RAW files - issue remains
• GPU acceleration enabled - issue occurs
• GPU acceleration completely disabled - no improvement
• Camera Raw cache has already been increased

The computer is otherwise high specification and Lightroom reports that full GPU acceleration is supported.

The key symptom is that after selecting the next photograph, the Basic adjustment panel is actually disabled/greyed out for several seconds, rather than simply the image preview taking time to render.

This also appears to affect workflow actions such as Paste, where the first click can sometimes fail while Lightroom is still loading the newly selected photograph.

Please investigate Develop module image-to-image switching performance in Lightroom Classic 15.5.1.

Many thanks :)