I use EAC to extract audio CD into CUE+WAV combo. EAC uses my system default language for its encoding, and this causes issues when I try to convert tracks on LInux using Flacon.
Most tutorials I have seen are based on command line using iconv, and this isn't something I prefer. Today I found an GUI alternative.
On Windows, I uses Notepad++ for convert the default encoding to UTF-8 and this works great. On Linux I uses its equivalence, NotepadQQ.
To convert the encoding, you open the file with NotepadQQ. Unlike Notepad++, it may have a bit of problem on guessing the encoding. Fear not, you can pick the encoding manually using the option under
Encoding -> Interpret as ...
Once you can see the file as it should be, you can use the whatever encoding you like using the "Convert to" option under the same menu, e.g.
Encoding -> Convert to UTF8
I found this option more interactive, i.e. I can see if my guessed encoding is correct. However, if you have a set of files need to get converted, you may want to take a look at iconv. However for odd files every now and then, NotepadQQ gets my vote.
Hope this helps.