Identify what changed in the video
First distinguish spoken audio from written captions and translated titles. A dubbed voice changes what you hear, while subtitles change the text over the picture. Changing one should not be expected to restore the other automatically.
For example, a bilingual viewer may want English and Spanish originals while keeping the application interface in English. The interface preference alone does not express both listening preferences. Write down the languages you understand and whether the selected video offers an original or alternate track before changing several unrelated settings.
Use the appropriate preference or one-video control
The official help provides preferred languages under Playback and performance on the web and also describes a per-video Settings > Audio track choice. Adding preferred languages affects the documented translation preference; selecting a track answers what to hear in this particular video now.
If only one video is unexpected, inspect its available tracks first. If the pattern affects many videos, inspect the broader preferred-language list. The help says this setting does not change search results or recommendations, so it should not be presented as a way to reset the entire discovery feed.
Treat automatic dubbing as an additional version
YouTube marks auto-dubbed material and acknowledges that translations or rendered voices can have errors. If exact wording, names or tone matter, compare the original track where available rather than assuming a generated dub reproduces every nuance.
For a support report, retain the video URL, selected track, preferred-language list and playback surface. A missing alternate-track menu is different from a listed track that plays the wrong audio. This guide did not alter an account or assess a translation’s accuracy. It explains which control addresses audio choice, so interface language, captions and recommendation preferences are not used as interchangeable fixes.
Questions about this guide
Is preferred audio language the same as app language?
No. YouTube’s help explicitly separates those settings.
Can I change just one video’s audio?
Where alternate tracks are offered, use the player’s Audio track control.