Ive had my console since March and so far this has happened about 10 times to me.
I take one of my 2 controllers and hold the Xbox button to power on the console, and it wont come on. xbox led just blinks.
When this happens, I'm ***. If I try the 2nd controller, same behavior.
I power on the system manually and it comes up, resumes to dashboard, etc.
However controllers will not sync. If I hit sync on the controllers and system, refuse to sync. I even plugged a controller up via USB and still would not sync.
Only once did I power off and back on the system and they worked.
Typically I pull the power plug out, no wait, and plug it right back in. Boots up, I power on a controller and auto syncs.
This is incredibly tedious.
I have some usb only mini controllers I'll try next time, but not sure if that makes a difference.
I also recently got a Kinect, sadly not advertised as refurbished, but it was. So I tried out of 6 times to get it to turn the console on, but often doesn't work. I now wonder if the issue is also related to the controllers.
Note, I only got the Kinect about 2 weeks ago and have had this problem for 3 months, so definitely not related to the kinect.