I am trying to disable the NAT settings on my TP-Link WR642G

SOURCE: I am using two WAN

I'm a user 4 the same load balance product, your 2 ADSL lines must have difrent IP with difrent submask than the IP you assigned 4 TP Link-TL R480t+ (10.0.1.1 in Ur case), lets say 1st line connected to the Line through a Dlink router has an IP 192.168.1.1, this will be WAN1, its config will be as follows:
WAN Port: WAN1
WAN Connection type: Static IP
IP Address: 192.168.1.2
Subnet Mask : 255.255.255.0
Defult Gateway: 192.168.1.1
MTU Size : 1500
Pri DNS: (add the DNS here)
Sec DNS : (add the DNS here)

the second line shuld be the same way with difrent IP & difrent subnet (for example IP=192.168.2.2, Subnet Mask = 255.255.255.0 - for the router connected to the 2nd line IP 192.168.2.1 which will be the defult gatteway for WAN2)
hope this answers your question
Hosean Kobara

SOURCE: After using TP-Link TL-R480t+ Router Video streaming from internet at sites such as youtube does not work at all

Hi ,This is Clare Su from TP-LINK support technical force.To you issue,I have the following recommendations:1. try to use only one line to connect to the internet,and see if you can watch the video on youtube2.if you can see the video with one line connected to the internet.Then,you can get another internet line with the router.And you can try to set the rule to the website: youtube, let the flow from youtube come in and out just from one wan port.if you can't solve the issue with my recommendation,you can email me. I will help youas soon as possible.My email is:clare.su from tp-link.com