I have had the Studio 18|24 for a while, hooked up to a passive volume control / speakers...
The Studio 18|24 will not pass audio unless it arbitrarily has a USB connection established even if for a single second. If turn my computer on, turn the 18|24 on and establish a USB connection, then put my computer to SLEEP or SHUT IT DOWN, the audio will pass through to my speakers until I turn the 18|24 off.
Please remove the need to require any form of momentary/constant USB connection before audio passes through the interface, it's absolutely possible and would make my experience with this thing so much better.
Sometimes I just want to jam without my computer, or having to turn it on and off. It minimizes distraction as well.
Make sure to upvote this if you agree..