Narrative:

During climb at approximately FL280; we started hearing erratic electronic popping/squealing sounds over our headsets. The other airline (oal) pilot occupying the flight deck jump seat (air carrier Y captain) indicated that his audio control panel (acp) was not responding to commands. His mic had been in the 'off' position. I called dispatch/maintenance control (mxc) over radio and asked for advice on how to proceed. Mxc referred us to QRH page for 'unresponsive audio control panel'. In flight; the procedure was to place the acp in backup mode; which we did. There was no change to the acp. Mxc suggested continuing to ZZZ1 and writing it up on the ground; then ended our conversation over the radio. I continued the conversation over ACARS and expressed my concern that there was an electrical problem with ACP3; due to the nature of the sounds (sounded like electrical arcing or shorting wires); the flashing lights on the panel; and the interference with our comm-1 and 2. I asked for mxc's blessing to pull circuit breaker (circuit breaker) C18; which is referenced in the 'on the ground' part of the QRH reset procedure. Mxc would not give direction to pull the breaker but said 'it is up to you if you would like to pull the breaker'. After discussion with the first officer (first officer); and confirming with mxc that ACP3 is the only component powered by circuit breaker C18; I pulled the breaker. All erratic sounds and flickering stopped. We continued to monitor ACP3 for irregularities until landing in ZZZ1. Mxc explained on the ground; after completion of the flight; that they were unable to give direction not specifically provided for in the QRH. I expressed my frustration that I did not feel maintenance was supportive enough in providing information we needed to make a decision. I had to specifically ask what components would be affected by the circuit breaker. If we were about to experience a worst case scenario - an electrical fire in ACP3 - we wasted valuable time trying to pull information from mxc; instead of mxc offering what they could in useful; relevant info. Audio control panel-3 (observers audio panel).

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Original NASA ASRS Text

Title: An EMB-175 pilot describes his efforts to have Maintenance Control approve an inflight 'pulling open' of an Audio Control Panel-3 (ACP) Circuit Breaker (C/B) to stop erratic; electronic popping/squealing sounds over their headsets. Maintenance Control noted they were unable to give directions not specifically provided for in their QRH.

Narrative: During climb at approximately FL280; we started hearing erratic electronic popping/squealing sounds over our headsets. The Other Airline (OAL) pilot occupying the flight deck jump seat (Air Carrier Y Captain) indicated that his Audio Control Panel (ACP) was not responding to commands. His mic had been in the 'off' position. I called Dispatch/Maintenance Control (MXC) over Radio and asked for advice on how to proceed. MXC referred us to QRH page for 'unresponsive audio control panel'. In flight; the procedure was to place the ACP in backup mode; which we did. There was no change to the ACP. MXC suggested continuing to ZZZ1 and writing it up on the ground; then ended our conversation over the radio. I continued the conversation over ACARS and expressed my concern that there was an electrical problem with ACP3; due to the nature of the sounds (sounded like electrical arcing or shorting wires); the flashing lights on the panel; and the interference with our Comm-1 and 2. I asked for MXC's blessing to pull Circuit Breaker (CB) C18; which is referenced in the 'on the ground' part of the QRH reset procedure. MXC would not give direction to pull the breaker but said 'it is up to you if you would like to pull the breaker'. After discussion with the First Officer (FO); and confirming with MXC that ACP3 is the only component powered by CB C18; I pulled the breaker. All erratic sounds and flickering stopped. We continued to monitor ACP3 for irregularities until landing in ZZZ1. MXC explained on the ground; after completion of the flight; that they were unable to give direction not specifically provided for in the QRH. I expressed my frustration that I did not feel Maintenance was supportive enough in providing information we needed to make a decision. I had to specifically ask what components would be affected by the CB. If we were about to experience a worst case scenario - an electrical fire in ACP3 - we wasted valuable time trying to pull information from MXC; instead of MXC offering what they could in useful; relevant info. Audio Control Panel-3 (Observers Audio Panel).

Data retrieved from NASA's ASRS site 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.