Systems and methods presented herein provide for isolating an upstream noise source in a cable television network. In one embodiment, a cable television network is communicatively coupled to a plurality of CPEs through a node. The cable television network comprises a CMTS with a CPE polling module and a noise monitor communicatively coupled to the CMTS through the node of the cable television network. The noise monitor is operable in a band of frequencies unused by the CPEs for upstream communications to determine when noise in the band breaches a threshold level, and to indicate when the noise breaches the threshold level to the CPE polling module. The CPE polling module then polls each of the CPEs to retrieve transmit power levels and locations of the CPEs, and identifies the first CPE with the intermittently noisy connection based on the retrieved transmit power level and location of the first CPE.