I'm in Gilbert and I'm seeing very similar stuff. For about two weeks we've had extremely spotty internet whereas I tend to loose my solid connection 5-10 times a day. It is very noticeable as I work from home and it frequently interrupts calls. I see a ton of "US profile assignment change." in my modem. Sometimes up to two changes a minute. I escalated to Cox support but they were unable to help me.
I should mention, I have the 1gig service tier. I've never seen 1gig, but I dream of hitting it with all of my expensive network hardware ready to go :).