Intermittent DNS issues. Modem restart helps for awhile, but then it will do it again.

I'm in the 85635 area and I've been having this issue for about two days. It affects both my laptop and iPhone/iPad when connecting wirelessly. 

Other than unplug both the cable modem and router, let them sit, and then plug them back in, is there anything I can/should do? Are there issues in this area that would cause my intermittent outages? 

Thanks!