I read だいがくせい as "daigakusei"
But when I hear a recording I hear "dainaksei".
I read だいがくせい as "daigakusei"
But when I hear a recording I hear "dainaksei".
I'm no expert on these matters, but I noticed this difference from living in Kansai and living in Tokyo. It's likely exactly what chocolate and oals linked with the nasal sounds.
I lived in Kyoto and while studying intensive Japanese at Doshisha University, I had a teacher from Tokyo. Until this teacher I didn't realise there was a difference between pronunciations as I took the Kansai pronunciations of polite Japanese to be normal.
However, when the teacher from Tokyo started her class she identified the difference in pronunciation. It was mainly related to the nasal pronunciation of words from those in Tokyo versus those in Kansai/other.
Recently, I spoke to a friend in Tokyo the other day about this and he had no idea that he was pronouncing words with the nasal "g". I verified with my other friend from Fukuoka (we were all having dinner) and she agreed.
So what you're hearing could possibly be a Tokyo "accent" of the nasal pronunciations that many people from Tokyo don't even know about.