Photos show in slideshow - Cannot find them on WDTV

I have the WDTV Live hub and amongst other things have all of our photos on there.  When the photos are playing a slideshow there are some photos on there that I want to remove but when I browse the WDTV hub from my mac I cannot find them to delete.  I can browse to them on the device itself but there are too many to delete individually on there.

Any ideas?

press ok while the photo is displaying you can remove the file from the WD TV Live Hub afterwards