Your mileage may vary, but....
I had the exact problem you describe when I was using a cheap
modem in a place where the phone lines were very noisy.
If the cause of your problem is the same as mine was, you have two
choices: either get the phone lines fixed (in my case, this was
not possible because the problem was in the trunk lines
going in and out of the town I was in) or else buy a better modem.
Steve
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One only needs two tools in life:
WD-40 to make things go, and
duct tape to make them stop.
-- G. Weilacher
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>I had the exact problem you describe when I was using a cheap
>modem in a place where the phone lines were very noisy.
You don't happen to live in an area with lots of thunderstorms?
I had a similar experience and it took Telcom to come and fix
it - some of their exchange equipment had been hit but wasn't
totally broken yet (only down to +- 9600 bps).
Lotsa Luck,
Gerd