ATM Cell Header errors on my AT&T wireless gateway

[Zombini]

I've had 117,000 cell header errors in the last 24hrs, it is currently 4:35pm where i am, and things were fine until today. Internet is extremely unreliable and i'm not sure if i can post this in one try.

EDIT: i went outside to check our connection, nothing near that can cause interference and the phone box is sealed, so checking for corrosion is not going to happen. I think the cause might be that the line that goes to the gateway from the phonebox is compressed because my parents ran it in through a window and shut the window on it. I keep telling my parents to have the AT&T techs to come and check the lines for corrosion/damage, but they don't want to pay for it, even though i think the service is free.