My backup RT-AC68R wouldn't boot up after a month or two sitting on the shelf, and I wound up going into Rescue Mode and re-installing the firmware. It appears to have been successful (after a few tries) and now comes up with the GUI login screen. But the default username and password don't work. admin/admin is what the ASUS user's manual says, and what I've always used... I tried both latest RMerlin and ASUS stock firmware, same thing. Anyone have an idea what's up? Hate to trash it for want of a password... Thanks!