Abstract: A disturbance detection and fast re-train method and apparatus configured for use in a multi-channel communication is disclosed. During data communication disturbance detection occurs by monitoring error rates or other factors, such as crosstalk profiles. Upon detection of a disturbance, the system generates and transmits a line upset condition signal to an opposing terminal and monitors for a similar response from the opposing terminal. Channels which fail to convey such signals may be switch out of service. The signals received via the channels may be utilized as training signals to thereby yield a new crosstalk profile. The new crosstalk profile is processed to establish one or more new multiple input, multiple output filter coefficients, bit loading settings, and gain level settings. These new settings may exchanged with the opposing terminal. In addition, channels which, although transporting signals, yield CRC error rates over a pre-determined threshold, are removed from service.