I just had this same issue. Hourly disconnects. I'm on Bright House Cable 30mbps. The Modem/Router they provide was giving a lease for 3600 seconds and then renewing. I just set up the 'fix' talked about, manually setting a static ip address. After saving the config and reconnecting, the lease time given changed to 604800. Would prefer an infinite lease, but if this works it is better than an hourly reset.