"The road is wide."
The Korean text to speech software used on the site isn't the best by any means. In fact, it's pretty bad.
But a reason why ㄴ can sound like ㄷ is related to tongue positioning. When I pronounce "d", my tongue touches the roof of my mouth close to the teeth and when I make an "n" sound, my tongue touches further back in the softer areas.
But Koreans pronounce both ㄴ and ㄷ with the tongue touching the front teeth. And both letters are pronounced by them with the tongue a bit softer against the roof than I would for "n".
It's really common and Koreans who do it likely don't even notice they're doing it.