A low power level is an indication you are on the wrong tap in the cab and would need a technician. Jump on the newsgroups and they will book one for you, without the need to call up. Rather book it now than suffer slow speeds or connection drops.
Just make sure the modem doesn't have an attenuator on the back, between the coax and the modem. If it does, just take it off and see how the power levels are.
