How about a .wav file for what team wins? You set the cvar for how many points before map change. Well if you get those certain amount of points it says "___ team scores" then it switches map. You could add a .wav that says "____ wins the match" or something like that. Little thing which really has not great advantage to add but I thought it might be cool hahah. :p
Also, the wav error is fixed, as you stated. But just telling you for sure after testing that it is fixed.