Questions about previous experiences are a given, and get quite specific. I was also asked to describe audio specific techniques. They do this to weed out those who apply for the job without having a good knowledge of signal processing techniques, which appearently are pretty common. Other questions include specifics of C++ and multi-threading, not only concerning "simple" mutex-locking but also more advanced topics, like atomics. They didn't ask any "riddle" questions, which can always be taken as a good sign.