A perfect storm of problems has formed around the mass media company Viacom. The company has long depended on revenue from its cable networks, and three of them -- Nickelodeon, MTV and Comedy Central -- have all been underperforming in recent years. Netflix is part of the problem, as old shows that used to be guaranteed winners on cable are now being streamed online instead. The numbers for reality TV are also down, which hits MTV especially hard. Comedy Central is facing its own problems with its Daily Show host transition. Viacom has taken a $785 million write-down, as well as dealing with layoffs and reorganizations within its companies. The owner of Viacom, Sumner Redstone, appears increasingly frail, and the future for the company in a post-Redstone world remains unclear.