Channel information is accessed that identifies a plurality of channels, and for each channel a multicast address to which packets carrying channel content are addressed. Multicast data rate information is obtained from a plurality of routers that identifies, for each respective router, a real-time data rate of data addressed to a multicast address being routed by the respective router. It is determined, based on the multicast data rate information, that an output channel data rate of a first channel of the plurality of channels is lower than an expected output channel data rate that corresponds to the first channel. Information indicating that the first channel has an output channel data rate that is less than the expected output channel data rate is presented on a display device.