A method in a first unit for determining a location of deteriorating hardware in a communications system, the communications system comprising a first and a second unit (101, 105) and a third unit, the second and the third unit communicating with one another over a wired communication link; the second unit comprising a second unit transmitter, tx,; a second unit transmit feedback entity, txfb,, providing a transmit feedback signal associated with a signal level of a transmit signal of the second unit transmitter, tx, at a position close to the second unit transmitter, tx,; and a second unit receiver, rx, the third unit comprising a third unit transmitter, tx,; a third unit transmit feedback entity, txfb,, providing a transmit feedback signal associated with a signal level of a transmit signal of the third unit transmitter, tx, at position close to the third unit transmitter, tx,; and a third unit receiver, rx,; the method comprising: - monitoring and obtaining (1301, 1302) signal level information over a period of time concerning - a signal A constituting a transmit feedback signal of the second unit transmit feedback entity; - a signal B constituting a difference signal based on a transmitted signal pertaining to the second unit transmitter and on a received signal pertaining to the third unit receiver; - a signal C constituting a transmit feedback signal of the third unit transmit feedback entity; - a signal D constituting a difference signal based on a transmitted signal pertaining to the third unit transmitter and on a received signal pertaining to the second unit receiver; - a further difference signal E based on said difference signal B and said difference signal D; wherein when a deviation in the monitored signal levels has been detected, - determining a location of the deteriorating hardware by comparing the deviation in monitored signal levels to known signal deviations for various locations of the deteriorating hardware, wherein the location is in at least one of the wired communication link, the second unit and the third unit. a second unit transmitter, tx,; a second unit transmit feedback entity, txfb,, providing a transmit feedback signal associated with a signal level of a transmit signal of the second unit transmitter, tx, at a position close to the second unit transmitter, tx,; and a second unit receiver, rx, a third unit transmitter, tx,; a third unit transmit feedback entity, txfb,, providing a transmit feedback signal associated with a signal level of a transmit signal of the third unit transmitter, tx, at position close to the third unit transmitter, tx,; and a third unit receiver, rx,; - monitoring and obtaining (1301, 1302) signal level information over a period of time concerning - a signal A constituting a transmit feedback signal of the second unit transmit feedback entity; - a signal B constituting a difference signal based on a transmitted signal pertaining to the second unit transmitter and on a received signal pertaining to the third unit receiver; - a signal C constituting a transmit feedback signal of the third unit transmit feedback entity; - a signal D constituting a difference signal based on a transmitted signal pertaining to the third unit transmitter and on a received signal pertaining to the second unit receiver; - a further difference signal E based on said difference signal B and said difference signal D; wherein when a deviation in the monitored signal levels has been detected, - determining a location of the deteriorating hardware by comparing the deviation in monitored signal levels to known signal deviations for various locations of the deteriorating hardware, wherein the location is in at least one of the wired communication link, the second unit and the third unit.