Intermittent Internet last few days?

Since Tuesday, my Internet has been intermittent (like the Cox advertisement says DSL is - up and down in the desktops ) from about 12 Noon until 5 or 6pm.  I live near Penn Square in Okla City.  Has anyone else been having problems?  I have called tech support each day, but have not really found an answer, other than they were upgrading - that might be causing it.  Since I am installing a new Arris/Motorola SB6141 Modem on next Tuesday, I don't want to place a service call, until I determine it the new modem might help.  it's very irritating tho.