Why would this sentence not simply be "Sei sola?" What is the "da" for here?
The "da" in this case introduces an adverbial modus locution; simply put "sei sola?" is literally "are you alone?", "sei da sola" is literally "are you on your own?". Not much difference, really, so both are just fine.
It was very difficult for me to make out what she was saying. Is anyone else having this problem, where occasionally the clarity is less than optimum?
That's being generous! I find the Italian TTS consistently underwhelming, garbled and choppy. Understanding where the stress is on a word is sometimes downright impossible.
Not that any TTS can really replace human speech, but there must be something better out there...
Really? Are you using headphones or ear buds in a quiet environment? (I use Sennheiser in-ear buds.) I find the Duo Ita audio absolutely outstandingly good. Each syllable unambiguous - if you have to go to the slow mode. You may note I have had plenty of practice listening to two other Duo languages. Italian is way the best, I find !
Not everything has to be full of innuendo. As a single parent, I sometimes get asked this- with the meaning- is it only you looking after the kids? It could be someone talking on the phone to their granny, and expressing concern. Overall, though, it's maybe a bit of a dramatic way to say it in English. It sounds like a spy story.