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MODEL-SPECIFIC DIAGNOSTIC

Diagnostics / Promethean / ActivPanel 9

No sound from an external source

The ActivPanel 9 displays the external source image, but no audio is heard.

Applies to this documented familyActivPanel 9, ActivPanel 9 Premium

Likely causes, most useful checks first

  • Source or panel is muted.
  • Wrong playback device selected on the source.
  • An adapter or cable does not carry audio.
  • Audio is routed to another output.

Safe checks

01

Check both volume controls

Confirm the panel and source are not muted and set both to a moderate level.

What the result means: Avoid maximum volume while testing.

02

Select the display as playback device

On the source, choose the HDMI or USB-C display audio output associated with the panel.

What the result means: If sound starts, the fault was source routing.

03

Test panel-local audio

Play an approved local system sound or media source through the panel.

What the result means: Working local audio points to the external source, adapter or cable.

04

Bypass adapters

Use a direct known-good audio-capable HDMI or USB-C connection.

What the result means: If direct works, replace or reconfigure the adapter/dock.

Sources

Reviewed under the BoardFaults safe-external-check policy · risk class: low · updated 2026-09-03