For support staff, once... Or never. After our way year I was advanced from part-time to full-time and given a salary. 2 years later when I asked for another raise, I was informed that support staff (i.e. Anyone who isn't sales) are not allowed to get paid more than a certain salary, and there was zero opportunity for advancement either. I loved working there, until I found out I hit my glass ceiling after just the first year.
If you were in charge, what would you do to make Cumulus Media a better place to work?
Take a step back, push your ego aside, and REALLY listen to your employees. And treat each and every single one of your employees with respect, regardless of their position, seniority, race, age, or gender. I have worked at so many other companies and have seen high functioning work environments. Happy employees make better, more efficient workers.
Company culture starts with the leadership. You can't just buy people food, give them free tickets, host events, or have "fake" feel-good meetings. Show your employees that they are important and valued, and maybe you won't see so many of them leave. Be transparent, and actions speak so much louder than words.