A Memory Called Empire is a science fiction book about Mahit Dzmare, an ambassador sent from her home (a space station, Lsel) to the neighboring empire when the station's previous ambassador was found dead. The position is important because Lsel is an easy target for the empire's expansion, and it's the ambassador's job to try and keep that from becoming a reality. The book itself is mostly about political intrigue, as Mahit is racing to figure out why her predecessor died and whether she's in danger, all while the situation at the empire's capital continues to destabilize.
I ADORE the Imago machines and their influence on the story. Because Lsel is such a small station they developed a form of technology that permits taking an 'imprint' of a person's psyche and memory. As people mature in the station's society, they take aptitudes to slot into a role and then acquire (one of) that role's imago lines, so an ambassador isn't just an ambassador, she's an ambassador carrying some of the traits and memories from each of her predecessors. It allows for a lot of exploration into the concept of identity in the book, and I think the author does marvelously.
Gideon the Ninth has been mentioned in other threads recently, but I'll just quickly say that the audiobook's narrator is divine.
Only the first few of the Culture series books are available in the US for audiobooks for whatever reason, but I thought they were pretty good.
Seveneves and The Diamond Age are both narrated well, although that's probably true for all of Neal Stephenson's books since he's a pretty big name.
Phoenix Extravagant is a fantasy book rather than sci-fi and I'd recommend its narration as well. I loved the book too! It follows a third-gendered painter in a kingdom that has been recently occupied by a neighboring empire (it's very much modeled after Korea being occupied by China). Jebi, the artist, is reluctantly drawn into a conflict between the occupying forces and the revolutionaries.
All of Ann Leckie's books are worth listening to. I particularly enjoyed Provenance, which stands on its own although it shares a universe with her Ancillary books.
I could go on for ages but those all come to mind right away.
