Coley is frequently mentioned as a cheap local fish. Locals confirm that coley was pretty much unknown in Cornwall in 1936 - far more likely would be ling or pollack. Additionally, "starry-gazey pie", of which the fish was to be an ingredient, is unique to Mousehole, about 30 miles from the supposed location in the film.
While Andrea is playing at the local party, another violin appears in the lower right hand corner and is being played at the same time that Andrea seems to be playing, but there's only one violin heard at the time. Could it be that the "real" violinist was captured on film by accident?
Andrea peels potatoes and bowls the bowling ball left-handed but plays the violin right-handed, as many violinists may do with right-handed instruments, but it seems a bit strange that the other actions are shown as left-handed.
After having his portrait Portrait drawn by Olga. Andrea walks out with his violin under his arm upon, arriving back to the sister's house he opens the door with both hands the violin is unseen. Andrea goes upstairs and his heard playing the violin.