I don't know if this issue has already been addressed, but I wonder if it's a VS bug or a failure on Last.fm's side. It is a little annoying when I have e.g. "Dawid PodsiadÅ‚o" (instead of Dawid Podsiadło) on my top artists page. Btw, i love the site and use it daily :)
I'm not sure if this dev is still active, but in the meantime I've been using Discographic on iOS. It scrobbles unicode correctly and you can scrobble A/B sides separate which is pretty cool. Worth checking out if you don't want to wait to listen to Motörhead haha.