For a long time I was using a patch panel to interconnect my receivers audio output to one or another modem or digital decoders. Then I found the F4AVI ham radio site on which an TEA6420 based design was discussed. The I2C driven stereo 5x4 audio matrix TEA6420 gives me all the functions required to design the electronic patch panel I always dream about.
In the current design, I use both left and right channels. The left channels are externally connected to CINCH like sockets while the right ones are connected to a small monitoring audio amplifier through a rotary switch.
As the matrix input/output lines capability was to small for my needs, I chose to use two TEA6420, each of them dedicated to one receiver rack.
The current configuration offers two 5 inputs by 4 ouptuts matrix that can be locally or remotely configured through the RS-232 serial link and a small Windows software. A manual switch arrangement has been designed to swap between 2 channels.