The letter o with umlaut (ö) quite frequently appears in German languages.
I do not know where the clip comes from, but the below is the explanation from Wikipedia.
Ö in other languages
The letter ö also occurs in two other Germanic languages: Swedish and Icelandic, but it is regarded there as a separate letter, not as an umlauted version of o. Apart from Germanic languages, it occurs in the Uralic languages Finnish, Karelian, Veps, Estonian, Southern Sami, and Hungarian, in the Turkic languages such as Azeri, Turkish, Turkmen, Uyghur (Latin script), Crimean Tatar, Kazakh, and in the Uto-Aztecan language Hopi, where it represents the vowel sounds [ø, œ]. Its name in Finnish, Swedish, Icelandic, Estonian, Azeri, Turkish, Turkmen, Uyghur, Crimean Tatar, Hungarian, Votic and Volapük is Öö [øː], not "O with two dots" since /ø/ is not a variant of the vowel /o/ but a distinct phoneme.