Hi to you both, and thanks for your quick responses!
I've already tried removing the mods, repairing the game and deleting the cache files. I had only bought the game only recently and have got the latest updates - I've also tried deleting/selling and replacing the items in question, to no avail. Equally, a different family / new game didn't fix the issue either.
Sorry to be such a downer!
Thanks,
Sapipsmu93.