NYC Dial up Impossible

[Msol]

I am going on my third month of not being able to a use a local access
number in New York City and getting nothing but a runaround from IDT
tech support. My problem? I moved ten blocks away to a hi rise building
in Manhattan. In my old building I connected 9 out of 10 times. Now,
IDT's New York access numbers (including brooklyn, bronx etc.) virtually
never work; when I do connect (maybe 1 out of 20 tries) the browser is
so slow as to be useless. Additional facts:

* I CAN connect to the New Jersey IDT access numbers – they work fine
* I CAN connect to the New York access number of another ISP in
Manhattan (newyorknet) – again works fine
* Bell Atlantic says the phone line checks out ok
* I've had the same problem on my old and new computers and on both
phone jacks in my apt.

I contacted IDT tech support 15-20 times. They suggest a variety of
extra strings to add to my modem config. – none of which works.
Apparently, the problem is with the lousy server modems used by IDT
which can't handle the lower bandwidth of the shared phone system in my
building. Yet there are hundreds of hi rise buildings in Manhattan. I
can't believe my building is so unique.

If IDT can't make it in New York…

I am seriously fed up but switching ISP's will be a great hassle. Anyone
have advice or should I just move on?

Mark