US Robotics 56k Voice PCI Modem

I bought my Dimension 4100 PC in March 2001.  I have started to have problems with connecting to the Internet (dial up).  The modem never connects first time, says it cannot find a dial tone.  I have to unplug the cable and try again.  Soemtimes it works, althought most of the time I have to unplug and reconnect 5 or 6 times to get a connection.  The wall socket is working because I can plug in my work PC and it connects first time.

 

Has anyone experienced this problem?

 

The modem is a US Robotics 56k Voice PCI and the model number is 3CP3298-DEL.

 

Many thanks .........Stephen