RDK-03033

I am getting multiple RDK-03033 errors, requiring the box to be unplugged and restarted.   It started a few days ago and is now an hourly event.  When we called Comcast last night, they tried to convince me it was an internet issue with a second wireless network that is used for a computer back up (time capsule) but doesn't use the internet.  The other problem is our Comcast router is set to a 2.4 and a 5.0 networks and they say I should eliminate them and make one.  Since this issue is new and that has been how our wireless has been set up for years, I don't buy it.  

I have reset the gateway and I have done a system refresh and it hasn't solved the issue.   There are no service outages in the area.   Any ideas?