I'm running a cascaded 24AI as master, with a 16AI as slave. I can set monitor levels for the guys in the band (Aux 1, Aux 2, etc) manually on the boards with no problem, including between boards. Universal Control (I'm using 1.501, "Surface", on a hard-wired Mac - and also on a Macbook over wifi) allows me to access either the 24AI or the 16AI without difficulty, but not both at the same time. This is a problem when trying to remotely adjust monitor mixes - only the 24 has meaningful Aux channels. So if I'm logged into the 24 tab using UC, I can't "see" any of the channels on the 16 to set their levels in a monitor mix. If I'm logged into the 16 tab using UC, there are no Aux channels corresponding to the actual monitor channels, so there's no way to adjust monitor levels on the 16, either.
The PR pitch on cascading is that it acts like a single, larger board - which is true from a hardware perspective. The software story is very different, though, and much less user friendly. I understand the RM mixers have the ability to access all combined channels as one combined board via software, and I'm hoping that same ability appears on the AI mixers as soon as possible.
The goal would be ultimately be to have all 40 channels (in my case, although all 64 channels if two 32AIs are cascaded together) available within a single window, and directly accessible through UCAI at the same time. The ability to set monitor levels remotely is a fairly basic ability as far as what I need from my board, and I'm currently blocked from remotely setting monitor levels for 16 of the 40 channels on my board. I'm behind the drums when we rehearse and perform, not at the board, so I can't physically be setting levels directly on the board - I need UCAI to be able to handle this.
I've been on the help system and on the phone with the tech support guys, who are great - and this is a feature that has no workaround - it needs a software solution. Please please please...