Only one of those jacks is for the phone line, the other is for an external phone so that you don't need to put a splitter on the line. If you look carefully at the jack one end says line and the other says phone, or they have a picture of a wall jack and a Phone right next to the jacks.
Try plugging in a phone to the phone side and see if you still have the problem.
If what you describe is truly happening then it is time to replace the modem.
You could try using a splitter to run the phone line into each side, that way you never have the line in the wrong place.
Ok this has been happening for a while on my creative modemblaster which has its drivers updated by the way. There are two inputs for the phone line, each time my modem dials out whether it be a successful dial or not it switches to the other input, the one where the phone line is not in. So this leaves me waiting for a dial tone when i hit sign in, and if i dont hear one i must put the phone line in the other jack as soon as possible and then it will start to dial. Anyone know how this happened? thanks!

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