An apparatus includes multiple media processing modules and a control unit. The media processing modules are configured to exchange digital media signals over a shared bus. The control unit is configured to determine a desired connectivity scheme among the media processing modules, to adaptively define, based on the desired connectivity scheme, connections that transfer the media signals among the media processing modules over the shared bus, and to instruct the media processing modules to establish the connections, by communicating with the media processing modules over a control interface that is independent of the shared bus.