Mixer and multiple
You'll always need to be able to split and sum signals... and it happened that I got a small (16mm) empty space in the modular. This is a 1+4 to 4 buffered mixer and multiple. It mixes up to 4 signals and distributes the mix to 4 independent buffered outputs.
Unfortunately there are no building instructions for this module, but at least you'll find the schematic, some photos, and some comments.
The muxiple under construction.
The finished muxiple, mounted in the modular.
That's it! Have fun, mix and split your signals!