My sister gave me an iPad air that was stuck in this sort of "Error 9" loop. She told me something about it freezing during and update and now, this. I messed with it for weeks, googling and reading and even got close to paying for a few (likely scam) programs that promised to fix it. Then I came across this useless youtube video https://www.youtube.com/watch?v=16hwbZhc... And for the first time in my adult life, a YouTube comment actually had value. Mr Jose Brun suggests to plug something into the headphone jack while performing a restore through iTunes. Like any of you, I rolled my eyes. But also, it's easier than taking it apart and looking for hardware to fix. It worked. I honestly barely believe it myself, but the iPad is back and working. So if you're tinkering with this kind of problem and your iOS device still has a 1/8 inch connector, plug something into it and see if that fixes it. If anyone out there knows why the heck this worked, I'd love to know.