Elite no custom images

Up until just now my Elite had been stable for a while. But after a quick little change to one of my activities, the remote no longer loads any custom images - no custom backgrounds, no custom icons. They’ve just gone.

I’ve tried syncing from USB, from the iOS app and from the remote itself, but nothing brings them back.

When I do a sync on the remote, it seems a lot quicker than it used to be - it jumps from 14% to 26%, then up again to 40-ish. It never did this before - in fact it used to stall for a while on 48%. This change leads me to believe that it is skipping over custom images, which is what was taking it longer all the previous times.

Any ideas what I might do to fix this?

Edit: all the custom icons are still showing in my iOS app, so I’m pretty sure it’s the remote at fault.