I have 2 questions today 
the first has been asked I think I already have the answer myself but you never know, I have an iPad, I have music on it, I have the cable to the USB-b from the mixer, so I use the sound card of the mixer, which is completely fine, but I can’t support recordings with USB or playing music via the USB ‘SQdrive’, for example. I don’t think this is allowed? or is there a way?
SQ can do either USB out or SQ Drive. Qu can do both at the same time.