Mnemix is a Keyframing Mixer inspired by Mutable Instruments Frames. It is a four mono input one stereo output mixer where you can store 8 different "presets" of level and pan for your instruments and then scroll through them abruptly (but clickless) or smoothly morphing through them.
start with Idx (index) 0, click on Write and set levels and pans of your 4 tracks anyway you want. Then move to Idx 1 and change levels and pan, continue until you fill all 8 slots (but you can use less if you don't need all 8). Then press Write again to stop storing (button unlit).
Now you can scroll through your mixing presets with the Idx knob. To achieve smooth fades between presets increase the Slew value. With minimum Slew you sharply switch from one preset to the other, always without annoying clicks.