Freezing while using embedding lyrics while having non standart characters in metadata or filenames.

[BohuslavChlubna]

@tranxuanthang this problem still persists with 0.9.0
I have just 49 tracks and everytime it just freeze at 34th. There is uppercase char č -> Č in track name. I am almost sure this is the issue. Many apps or webs have problems with uppercase letters with diacritics. And when I turn off embedding lyrics inside file, it works well.