Thank you for the question. The articles below may help you with the VoiceOver issue you are experiencing.
Thank you, Jason!
Your answer helps me, but it doesn't really cover my needs. I may go through all my music and define the correct language for every song that is not in English, but it isn't really tempting to do this with approx. 1000 songs. (My music collection consists of several languages.) My point was that this was done automatically earlier for my iPod Shuffle, but not at all with my new Nano 7th gen. So I still wonder if this can be done automatically.