Older cable modems were much hotter than many of the newer ones. Seven years is a long time, however, some have lasted longer.
Try unplugging it and remove and replace the cable at least 3 times, and If you have a CAT cable running to the computer do the same to it at both the modem and computer; make sure the modem is unplugged and the computer turned off before you do this.
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If you continue to have trouble, call your cable modem and ask for a tech to come to your house and check the modem, and while he is there, have him check the cable from the street to your house. If your cable company does not want to do this, tell them you will get another supplier.
If you cannot get a different cable or DSL supplier, ask the cable company if you can purchase your own modem, and take your monthly modem charge off your bill.
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