Narrative:

After pushback; when the ramp agent disconnected the headset; there was a very loud static squeal making the intercom and radios unreadable for several minutes. The ramp agent was called back to aircraft and asked to plug in again. After disconnecting; the radios and intercom returned to normal. Taxiout was okay; but once we were cleared for takeoff; as power was applied; the squeal returned making the radios unreadable. We exited the runway. After further troubleshooting we attempted another takeoff; but the squeal returned. After exiting the runway we returned to the gate for maintenance to investigate. Takeoff power never got set so a rejected takeoff was not an issue. After further troubleshooting aircraft was dispatched under MEL 23-43-XXXX aircraft flown to ZZZ with no further problem. In ZZZ; maintenance replaced the headset jack assembly. As soon as ramp agent plugged headset in the squeal returned at the same volume as before. The discrepancy was re-entered in to the logbook for further trouble shooting. I was pressured to take the aircraft. It was not until I explained to the maintenance supervisor that I was not happy to take the aircraft until further troubleshooting had been performed did they change the audio management unit in the electric and electronic compartment. The aircraft was returned to service with no further problems noted. Total delay [was] 3 hours and 30 minutes.

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Original NASA ASRS Text

Title: The Captain and Dispatcher describe the radio and intercom issues on an A321 after the pushback crew disconnected the headset. The problem returned when the throttles were advanced for takeoff; so the crew performed a slow speed reject. After troubleshooting; the Flight Deck to Ground Interphone system was deferred as inoperative. However; when the next station replaced the headset jack and the system reactivated; the problem returned. The system operated normally after the Audio Management Unit was replaced.

Narrative: After pushback; when the ramp agent disconnected the headset; there was a very loud static squeal making the intercom and radios unreadable for several minutes. The Ramp Agent was called back to aircraft and asked to plug in again. After disconnecting; the radios and intercom returned to normal. Taxiout was okay; but once we were cleared for takeoff; as power was applied; the squeal returned making the radios unreadable. We exited the runway. After further troubleshooting we attempted another takeoff; but the squeal returned. After exiting the runway we returned to the gate for Maintenance to investigate. Takeoff power never got set so a rejected takeoff was not an issue. After further troubleshooting aircraft was dispatched under MEL 23-43-XXXX aircraft flown to ZZZ with no further problem. In ZZZ; Maintenance replaced the headset jack assembly. As soon as ramp agent plugged headset in the squeal returned at the same volume as before. The discrepancy was re-entered in to the logbook for further trouble shooting. I was pressured to take the aircraft. It was not until I explained to the maintenance supervisor that I was not happy to take the aircraft until further troubleshooting had been performed did they change the Audio Management Unit in the Electric and Electronic compartment. The aircraft was returned to service with no further problems noted. Total delay [was] 3 hours and 30 minutes.

Data retrieved from NASA's ASRS site as of July 2013 and automatically converted to unabbreviated mixed upper/lowercase text. This report is for informational purposes with no guarantee of accuracy. See NASA's ASRS site for official report.