Modem can't dial, just static, at night

[sykoboy]

Between about 6:00 PM and midnight or 1:00 AM, when I try to connect to the internet (Earthlink Dial-up, U.S. Robotics 56K Fax PCI internal modem), instead of the usual dialing and connecting sounds, I hear crackling static that starts immediately and get a "no dial tone" message. Occassionally, in the midst of the crackling static, I will hear the modem dial and attempt to connect, but it fails. The problem does not occur during other times of the day. During the times when I have the connection problem, my phone works normally. I tried using another phone jack in the house, and got the same problem. I have not changed any settings, etc., lately.
Since this problem seems to happen before the modem even dials, it doesn't seem to be a problem on the Earthlink side. It seems especially strange, since it essentially only occurs during the aforementioned time of the evening and night, and the phone seems to be fine during those times (no static, etc.).
Any suggestions would be appreciated.
Thanks.

[merlin_2]

unplug your phone........and connect to the main phone jack......do you have an extension lead that is connected to the modem.??.... if so>>.....does it run pass any electrical boxes??

[Cary_GRant]

go into your modem properties and uncheck that little box that says something like "Wait for dialtone before dialing" it may be the root of your woes.