No dial tone message on Laptop

HP pavilion ZE4200 with internal modem had worked flawlessly for 2 years.
Recently I have been getting "Disconnected for unknown reasons" about once a day. Today It gave the "No dial tone detected message" about 10 times even after rebooting twice and making sure I was connected with a good phone line.

I ran the virtual troubleshooter and it says the modem is fine and connected properly. The last time I rebooted and tried it, it worked.
Do you think this is a loose connection or a modem that needs replaced? should I pickup a modem that uses the PCMCIA Slot or maybe the USB?

I actually started taking the back off the computer but stopped myself when I thought of the downside of killing a very nice laptop with my clumsy attempts to fix something I know nothing about.

Any thoughts would be appreciated. Thanks

 

The modem started working again and seems faster than before. Maybe it got temporarily confused when I sat the computer on top of a large speaker. magnetic fields and such.

Wierd stuff.