Internet in and out randomly during the day.

Arris TM3402 all the lights are white.

So you don't lose any lights on the modem when you lose service? What about phone service? Do you lose dial tone? If so, check your event logs at 192.168.100.1 for any T3/T4 errors or anything else that is critical.

If the lights remain solid on the 3402, it means it still has internet try swapping the ethernet cable from modem to router, with a new cat5e

No, the lights don't change. We don't have a house phone.

That is odd. I thought the only way to get the TM3402 is to have Cox phone service. Do you just not use it? Either way, it seems to be effecting wired and wireless, so I wonder if it could be a issue with your router. What model router is it?

Try connecting a PC direct to the TM3402(don't forget to power cycle) for a bit and see if the internet cuts out then.

Anyone know if the TM3402 keeps event logs at 192.168.100.1?

Cox must have fixed my problem overnight. Did yours get fixed?