Yeah I totally know what you mean about actors having not the proper accent. When you don't understand the language at all, it seems impressive of course but when you do, lol, its another story.
Same happened to me with a song I love sung by Annwn (Douce Dame Jolie), which is an old french song and she singer is German. I was only able to detect heavy german accent and improper pronunciation when I myself was a bit good at French!
The song itself is amazing, try that here -