As I type this, I'm listening to Vivaldi's Concerto in B Minor for 4 Guitars and Cello, which is labeled RV 580 and has the title "L'estro Armonico No 10." This is the specific recording:
However, every Google result, Wikipedia result, YouTube search, etc. that I can find for "RV 580" lists it as a concerto in B minor for 4 violins and cello.
I'm under the impression that RV numbers are unique - if they're not, perhaps that's the source of my confusion. But if they are...why is this piece labeled for guitar on at least one recording and labeled for violins elsewhere?
I've listened to some of the YouTube recordings which are labeled as violin and it is the same music (though of course sounds quite different!)