1. go to the \data\sounds\events_dat_backup directory (f.e.: C:\Rome - TotalWar\data\sounds\events_dat_backup)
2. copy the events DAT-File in there and paste it in \data\sounds, overwriting the existing one (you should make a Backup-File of the one you are overwriting)
3. Get the original descr_sounds_music.txt file from an other installation of Rome (I took it from my EB-Installation); you find it in your \data Folder. Paste this File in \data of your RSII-Installation.
4. I deleted the descr_sounds_music.txt in \play_rome_one_turn as well (because that's the campaign I'm currently playing), although I'm not sure if this is really necessary.