iPhone and macOS · Research guidance. Instructions are based on publisher guidance; a UK IPTV account was not tested on this platform.
Persistence is a useful clue
If the same rain or noise sound continues through several programme titles, the source may be outside those programmes. Apple supplies Background Sounds as an accessibility feature on iPhone and Mac. The sound can be a separate device-generated layer rather than a fault repeated in every soundtrack.
Pause the programme once
At a comfortable level, pause the programme and observe what remains. If the background sound continues, inspect Apple’s Background Sounds control. That observation does not prove the feature is responsible, but it narrows the question. A clear next step is a short comparison with that named feature off.
Media interaction differs by device
On iPhone, Apple documents Use When Media is Playing and a Volume with Media choice. Mac has its own background-sound volume and stopping controls. Use the actual device settings rather than assuming an identical menu. A setting suitable for quiet work may be distracting when layered with dialogue.
Avoid changing the wrong layer
A subtitle language, programme soundtrack selection or streaming quality choice does not control a separate system background sound. Changing several of those while investigating the persistent layer can create new differences without answering the original question. Keep the programme unchanged during the source comparison.
Record the result rather than a diagnosis by guesswork
Say whether the sound remained after pausing, whether the feature was enabled and what happened when it was temporarily stopped. Restore the useful preference afterwards. These facts distinguish device audio from programme audio without claiming every stream was tested or every persistent noise has the same cause.
Questions, answered
Can the same ambient sound be independent of several programmes?
Yes. Apple provides a separate Background Sounds feature.
Does changing subtitle language control that sound?
No. It is a different presentation and audio layer.