Good Morning;
For some reason channels 9 thru 16 are dead. But not consistently.
The other day I had set up for an upcoming show and all worked just fine. Yesterday I went in to do some recording for a friend of mine and channels 9 thru 16 where dead. Tried everything (I Think). Moved inputs to channel 8…fine. Moved input to channel 17…fine. Did a hard reset no change. Shut down and restarted and it was fine. Any thoughts of what could have caused this?
Assigned to local, DSnake or USB inputs?
Dead, as in nothing on PFL/ solo?
Yes Dead. Nothing. Solo, etc. Nothing. Just 9 to 16. Pretty weird to me. And then to come back on when re-starting.
bad ribbon cable connection, send the unit back and get it replaced.
That was my first thought as well. I was just hoping it was something else. Thanks for your reply though.
sorry you are having trouble 
RIC4001, I have the same problem with yours. Channel 9-16 is dead on my QU-24.
Did you get it fix? What is the problem?
If the “gain knob” on the channel screen is not RED, you’re on a digital input instead of the local console input. Make sure that your inputs are all the same. I don’t know why things would change as a block, but it IS possible from the scant info given about the " problem" that no matter what the cause, the “fault” may simply be mis-assignment of input source.
Worth checking.
The likelihood of there being a problem is very small.
if it was me I’d pretty much guarantee that I’d misrouted or misassigned something
Do you have either a AB168 or AR2412 stage box to try and see if the channels 9-16 work via the stage box through the mixer. That would somewhat narrow down if it is a mixer input hardware problem isolated to channels 9 - 16 or a software processing issue with those channels. Either way it doesn’t fix the problem, just an experiment to try.
Or you could try USB inputs, from USB A if you have a previous recording you can use, or USB B if not.