@zeroxia: the font you use for the "Sans" family doesn't have the proper glyphs. You can either use another one with full coverage, or frankenstein it with a font editor to add the missing glyphs.
(I don't *think* the framework looks into fallback fonts for the UI, so, changing the symbol/i18n font shouldn't have any effect on this, but, hey, I've never terribly looked into this myself
).
EDIT: That, or figure out how the default dictionaries manage not to put the phonetic pronunciation at all in the popup
.