It can be used as a very flexible mixer as it can connect any input to any output the user wants and has a memory to remember patched circuits (it can also create or activate patches live via midi.

https://www.ericasynths.lv/shop/standalone-instruments-1/desktop-matrix-mixer/

It has been used very little (it's practically new) and has been bought from Greece (synthesizer.gr) 26/08/22 Features: All analogue signal path 16 buffered, DC coupled inputs 16 independent, buffered, DC coupled outputs 256 connections, each with 3 attenuation levels Random pattern mode with definable randomization area and density 254 pattern memory Pattern change via MIDI program change messages