sounds like your box failed to reboot properly after the software download. try unplugging it to reset. If that does not work call comcast for a box refresh if none of that works, time for a new box. those ones are old.
Dec. 30, 20012 I am also having the same problem on my two 8300 DVR, it happened after Comcast did an upgrade / downgrade I should say , since I did not have these issues of REBOOTING every 10 to 20 minutes. Please fix the problem.
Same problem here, I have two 8300 DVR and started having rebooting problems every 10 to 20 minutes, started having the problem after a current upgrade again from Comcast since , I have notice a new guide format and rebooting display on tv during reboot also no display showing on DVR box during reboot so Comcast did an upgrade or I should say a downgrade, Comcast please fix the issue if REBOOTING since a lot of customers are experiencing the same problem.
Dec. 30, 2012 my two 8300 DVR's keeps on REBOOTING after Comcast did an upgrade or I should say a downgrade, rebooting displays are now different mo APDL display on box now there is a 5 minute running time on Tv display that is why I know a change of programming has been done recently but since then the issue of REBOOTING happened, please fix the problem.