Is anyone else having difficulty hearing this at speed? Particularly the "duermen"? I had no idea what she was saying there until I slowed it down.
Two reasons, the first being that it's sort of a Stephen-Hawking style computer voice and will never sound perfectly natural. The second is that the way words flow together in Spanish is different than in English and it is typically spoken a lot faster, especially in certain parts of the world (in Chile they talk very fast, and I've heard that foreigners such as Mexicans have trouble understanding them because of the speed and the multitude of slang.