Compare interface feedback with media audio
Listen for navigation clicks or confirmation tones separately from dialogue in an authorised programme. Record whether the change affects one, both or neither. A programme and the application’s own interface feedback are separate sound sources even when they reach the same speakers.
Kodi’s audio documentation explicitly says GUI Sounds volume does not affect music or video playback volume. Its surrounding audio page includes other settings with different purposes, so the position of a slider in an audio menu does not make it a universal programme-volume control.
Inspect the selected control and timing rule
The GUI Sounds section also determines when interface feedback plays: stopped playback, always or never in the documented interface. A click disappearing during a movie can therefore reflect that timing preference rather than a failing output device.
Keep the exact setting label with the observation. If the task is changing movie volume, use the relevant playback or receiving-device control for the actual audio route. Encoded passthrough and decoded playback can have different control relationships, so document the selected output rather than assuming the GUI slider governs them.
Verify the intended listening result
Choose a comfortable level and compare the same brief passage while using the intended programme control. Check menu feedback separately. The comparison should answer which sound changed, without repeatedly increasing several unrelated controls until the result becomes difficult to interpret.
For help, report the Kodi version, output device, whether passthrough is active, the exact slider and when interface feedback is audible. A precise report distinguishes an intentionally narrow GUI preference from a media volume issue or a receiver-control problem. It also prevents normal interface-sound behaviour from being used as the only evidence that a programme’s audio output did or did not change.