I have not had time to do any additional troubleshooting, but, I did move the router from our basement to my first floor office to get better coverage on our second floor. We had a decent signal on the first floor prior to the move even though the first floor is where all the issues occurred.
Since the move, I've not had any complaints from my wife or daughter about the signal dropping off. Perhaps moving it further away from all of the electronics still in the basement (the cable modem, the digital phone modem and the Netgear switch) has something to do with it. Awfully coincidental.
I'm also wondering if perhaps moving it to the first floor and having an even stronger signal means it's less susceptible to interference from other neighborhood routers?
If the problem reappears my next step will be a factory reset with settings from scratch. Until then, I'm just going to leave it alone.
Any status on this? 