We just completed preliminary testing on Linux with the ConnectAUDIO 2/4 and it seems to be all working - audio and MIDI! Tested on Ubuntu 17.04, but should work fine on most major distributions, especially those based on Ubuntu such as Linux Mint.
The great thing about the ConnectAUDIO 2/4 is that it needs no control software at all, everything can be controlled from the front panel touch screen. So on Linux it should be literally plug & play. If you have been looking for a Linux-compatible iConnectivity interface this one looks like a good choice.
We will be continuing to test this in the next days, but so far, so good :-)
May the Force be with you!