Linksys Wireless Router :: EA6500 Won't Update Firmware?

an EA6500 router that has intermmitent connectivity issues.  Went into the configuration page and saw he was a couple versions behind on firmware.  Used the online update option, firmware downloaded and then indicated that router would reboot.  Did not power off router or leave the configuration web page.  Watched light go out on router and come back on, but the spinning wait icon never went away after 5 minutes.  Powered off and on and was back at the same point with the old firmware still.  Downloaded the firmware to local drive and applied from local file, but same results.  Waited 10 minutes this time.  Surely it doesn't take more than 10 minutes for the router to reboot itself from a firmware flash?
 
Gave up on trying to update firmware and configured wifi settings.  Left friend's house and then got a message about 15 minutes later that the router had locked up again.  If he pulls power for 2 minutes it will then work for another short period of time. 
 
Is there anything that can be done to try and restore normal operation to this particular router, or are these all signs of a hardware failure and the unit should just be replaced?