Impossibly high data usage

I have been fighting supposed high data usage. I unplugged all physical cables, and disabled wireless in my router. The only thing connected from Friday Afternoon to Sunday evening was the physical router. According to the Usage Meter for Cox, My usage over this period went from 308 gigs to 465 gigs. I have a D-link DIR-865L that used 157 gigs over 2 days by itself?? BTW I used this same router behind the Cox supplied router, that I never really used, and the usage was fine. When I got rid of the Cox Modem/router junk box and got my own Modem, this usage exploded to the tune of 37 gigs a day average. One day was reportedly 62 gigs in a single day, when I was 600 miles away. My Wi-Fi password is 47 characters long with cap and non-cap, numbers, and symbols. Every machine in the house was scanned with Spybot, Microsoft Security Essentials, AVG, Malware Bits, Panda, Norton system protection, MacAfee, and Trend Micro. All with negative results. Basically somehow an impossible amount of data usage is being reported on my account that cannot be accounted for. The router, with Wi-Fi disabled, should only check it's online connection to the internet and NTP address polling. All other services are turned off. Cox needs to have a LVL 4 tech support that you can get log files with source and destination MAC addresses so I can compare all MAC addresses in my network. I'm positive they won't, but it would be the smoking gun I need to prove the data usage is not on my end.