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As Kosmo writes in the duplicate: “These variants don't come from Yiddish, German, or any other language. It is simply a natural phonological process that occurs in many languages, often due to co-articulatory factors.” It also happens in words like tree in the unvoiced version. These are not different phonemes, merely natural allophones, and untrained native speakers are completely oblivious as to whether they do it or not (Kosmo is not untrained :). As a non-native speaker, you have to learn to hear the abstract mental phoneme, not the myriad allophones that don't matter.
@Lambie it's entirely believable. I once had a conversation stop in its tracks because my Greek conversation partner insisted that I stop saying "chrain" when referring to intercity rail transportation. Or chransportation.
@Lambie I can't believe that you have never heard this from any American. How do Americans you hear pronounce "Trump"? A couple of instances I found in a quick YouTube search: In youtube.com/watch?v=KRmnaszQRGg Joe Biden says 1:09 "transportation". In youtube.com/watch?v=61yTbx8IsCo Pete Buttigieg says 0:07 "entrusting" 0:23 "transportation".