Some times the TTS just decides to completely mispronounce a word, cut off early, or just not make any sound at all. It usually works out after reselecting the TTS model, and trying again.
I would say that 4 out of 10 audio generations has some sort of issue like this. It is still pretty good, but kind of annoying at times.
Here are some examples I stumbled into. I did have issues in other languages as well. Not just Norwegian.
I expect the TTS to pronounce the whole sentence correctly and consistently over multiple uses.