AV System Troubleshooting and Maintenance Flashcards

A motorized projection screen stops halfway during deployment and will not respond to further commands. The control relay is confirmed active. What should be checked next?

Answer: Inspect the limit switch settings and mechanical travel stops

Motorized screens rely on limit switches to define travel endpoints; incorrect calibration or a triggered limit switch mid-travel will halt the motor even with a valid control signal.

A Dante audio network shows intermittent dropouts, but only on specific subscriptions. The network switches are unmanaged. What is the recommended corrective action?

Answer: Replace unmanaged switches with managed switches and enable QoS/EEE settings appropriate for Dante

Dante requires managed switches with QoS configured and Energy Efficient Ethernet (EEE) disabled; unmanaged switches cannot provide the deterministic latency Dante needs, causing dropouts.

An HDMI extender over HDBaseT passes video but produces no audio at the remote display. The source device is confirmed to output audio. What is the most likely cause?

Answer: The EDID from the remote display is not being passed correctly back to the source, causing it to default to a format the display cannot decode

HDBaseT extenders can fail to pass EDID correctly, causing the source to output an audio format (e.g., Dolby TrueHD) that the display cannot decode, resulting in silence.

A conference room's AV system passes a periodic preventive maintenance (PM) check. Which item is most critical to include in a PM schedule for a high-lamp-hours LCD projector?

Answer: Replace or clean the air filter and log lamp hours against rated lamp life

Clogged air filters are the leading cause of projector overheating and premature lamp failure, making filter maintenance and lamp-hour tracking the highest-priority PM task for lamp-based projectors.

After replacing an amplifier in a 70V distributed audio system, several speakers produce very low volume even at full amplifier output. What is the most likely cause?

Answer: The speaker tap settings are set too high, presenting an impedance that is too low for the amplifier

In a 70V system, speaker taps set to higher wattage draw more current and reduce the effective impedance; if aggregate tap load drops below the amplifier's minimum impedance, output drops significantly.

A technician is troubleshooting a PTZ camera that has lost its preset positions after a power failure. The camera responds to manual pan/tilt/zoom commands. What is the correct resolution?

Answer: Reprogram and save the preset positions in the camera or control system

PTZ camera presets are stored in volatile or flash memory that may clear on power loss; the correct fix is to reposition the camera and re-save all presets through the control interface.

A newly commissioned AV system produces feedback during a speech. The microphone and loudspeaker placement have already been optimized. What is the next recommended step?

Answer: Use a parametric EQ or automatic feedback suppressor to identify and notch the feedback frequency

After optimizing placement, applying a parametric EQ notch filter at the feedback frequency or deploying an automatic feedback suppressor is the standard technique to eliminate feedback while maintaining usable gain.