Hi Guys, I just got my model 24 on the basis it would work on my old (yet more than adequate) studio computer which is a 2008 Mac Pro running El-Capitan. It does have USB 2 and It runs Ableton 9 just fine. I was hoping to use the 24 to multitrack in and out into Ableton. However, when I plug in the USB my computer doesn't read it as an audio driver anywhere. I tried it straight out of the box , and then the sd card update to the latest firmware and same problem. The model 24 does say usb connected when in storage mode and the usb light does light up. If I plug the usb into my 2015 MacBook Pro it reads it picks up the mixer straight away as Model 24. I really did buy this in the basis of being able to run it off my studio comp. Does anyone have any advice?