I also am having the same problem, i have tried to verify my files in steam, i also went to the full extent of un-installing all my arma 3 files, then un-installing Steam. then re-installing (64.9gb OMG) and the problem is still there!!!
i have waited for speech to start but it doesn't, also tried change/reduce the channel count in audio with no avail.
Has anyone found this problem and managed to sort it?
if so please could you post how you sorted this, its like it hasn't installed properly?