AT&T West → More Speed Cap Questions

A couple more speed cap questions for all of you.
I am currently capped at 384 down. I called Pac Bell provisioning and the tech guy reluctantly told me that my attenuation is 60db and my noise margin is 10 db. Should I continue to pursue getting my cap raised, or do the numbers above indicate that I'm stuck at 384? I'm a little less than 15,000 feet away from the CO.
To compound the issue a little more, Pac Bell is my CLEC, but Earthlink is my ISP. The guy at Pac Bell insisted that I need to go through Earthlink if I want to get the cap raised. I have little confidence in Earthlink's tech support at this point. Has anyone with an ISP other than Pac Bell been able to deal directly with Pac Bell when getting their cap raised?
Thanks in advance.

What the numbers mean
(stolen from Paladin)

Capacity Range 0 to 100 Lower is better, Ok as long as not topped out (100)
Noise Margin Range 0 to 31 Higher is better, looking for > 8
Signal Power Range 0 to 20 Higher is better
Attenuation Range 0 to 60 Lower is better

IMO, it looks like you're borderline. You could call ASI at 888-900-9933 option 2 and asked them to raise your cap. I suspect that you would have stability problems though.
--
This Space for Rent

go ahead. Just try it and if it doesnt work than switch back. They always try to be negative almost confusing. Just put your foot down and say do it and if it doesnt work Ill call you back.
--
Ya feel me knockin? Well let me in.

One more thing, Im 17800 feet away and get 646/110.After I had cap removed
--
Ya feel me knockin? Well let me in.