[garynitely]

not too dumbed down at all, my experience with this stuff is limited to following guides online, i'm just about keeping up with you as it is!

i feel like you hit the nail on the head again. i am almost certain that i scanned it into the library on the minipc directly from the external hard drive. i will rescan after adding it through smb (as it currently is on the Pi), so that both devices are looking in the same place. this is likely the cause, by the sounds of it.

i'd hoped to avoid rescanning my whole library as that means losing many custom settings such as movie sets. but another evening of organising is a small price to pay i guess. 

(full disclosure... i had no idea about the static IP address, I've fluked my way this far and have now just found an option in my router settings to 'Always use this IP address:' on the MiniPC and have told it to!)

thanks again, will report back, though possibly next week. fingers crossed