Identify what you want to improve
For a spoken explanation buried under background sound, inspect whether Voice boost is available. For generally uneven loudness across a video, Stable volume may be the control relevant to the problem. Neither feature is documented as available on every video.
Choose a short reference passage with both speech and background sound. Keep the main device volume comfortable while comparing the processing choice. Do not repeatedly raise the system volume to compensate for one difficult sentence and then judge the next loud section at that higher level.
Expect the two controls to interact
YouTube’s help places Voice boost in the computer or TV player settings, with the TV route under Audio. Activating it switches off Stable volume, although the guide says both controls balance quiet and loud sound. Stable volume is also turned off for YouTube Music and official music videos.
If you return to the settings and find Stable volume disabled, first check whether Voice boost is active. That is a more direct explanation than assuming the app lost your preference. When comparing results, note the active control instead of claiming that both were working independently at once.
Keep title availability and device controls separate
If Voice boost is absent, record the video and the receiving platform. Do not assume a Premium payment or an unrelated speaker setting creates a control that the current video does not offer. The service help describes it as a computer/TV feature with title limitations.
For a household handover, leave a simple note of which listening mode was selected and why. If the result sounds unnatural or less clear, compare the original passage with the feature off before changing other equipment settings. This keeps the decision grounded in the actual dialogue problem and avoids mixing app processing with a hardware fault.
Questions about this guide
Why did Stable volume switch off after I enabled Voice boost?
YouTube explicitly documents that automatic interaction.
Should every music video have Stable volume?
No. The help says it is turned off for YouTube Music and official music videos.