Depends on how much brain capacity I need. When I need to actually think, it has to be instrumental. So game soundtracks, classical music etc. Stellaris is one soundtrack I quite like for thinking. When it’s something I have to think really hard about, it’s music off though.

Otherwise, when I’m working on a repetitive, brainless task, it’s whatever I’m in the mood for. Metal, country, j-pop, post-punk… could be anything really.