Recording Audio from multiple audio channels of a Focusrite Scarlett

[vincenzo.trombetta@gmail.]

Hello everybody

I'm driving mad with OBS. That's the question:

I Have a Focusrite Scarlett 18i20 connected via adat to a Behringer ADA9200 for a total of 16 phisical channels
I some of these channels I've connected some synthetizers and an MPC one that drives all the sequences.
I Just want to do a live performance and I need to have all of these channels on OBS.
I've tried the ASIO plugin, the capture audio tool but when I have to select a device, OBS sees only Analogue channels 1 and 2.
How can I capture live this audio into OBS?
Please I'm quite an OBS noob so if you know the answer please be specific

P.s.: I don't want to pass through a DAW, just want to play ohisically the instruments directly from the sound card

Thanks in advance