I am not sure if VLC covers it, but I cannot open a .VOC file with that player. So, I request if anyone can find a way to create a .VOC plugin.
It seems it's not a common audio file, mainly because only a few has ever played and/or convert a .VOC file. Also, I believe it was compressed by the use of a RCA recorder. I don't know, because it's a file from a friend who doesn't have a microphone, just a recorder.
If it's possible, that's great! Sorry to trouble you.