Greek voice broken in High Sierra on the mac

Hello,

After I've upgraded to High Sierra, I have discovered that the Greek voice has been broken. Instead of reading text in Greek, the voice spells the text which makes it impossible to use it. I've reported the issue to Apple.. I've also reported it to Assistiveware who distribute Acapela's Dimitris voice for Greek but they are saying that on their computer the greek voice reads correctly. I'm totally confused not to mention the fact that I'm not able to read in Greek using the voice any more. Has anybody in this forum experienced this? I mean those of you who might be Greek speakers. I've been through all possible settings in Voiceover utility but to no avail.