One thing I noticed in-game (running Windows 10), is that I needed to switch from speakers to headphones. So, using the windows audio control, I made the change while Nova Drift was running. Most games I own will send audio to whatever destination the user specifies in their operating system, and I'm sure that's checked once on startup. The game might want to poll that resource once per few seconds or something. I don't think it would require a lot of overhead.
I'm not a huge expert on exactly which system resource needs to get pinged for the game's audio output to get moved. For instance, if I am playing a youtube video and running Nova Drift; audio output to my headphones and switch from headphones to speakers, Youtube will make the switch, Nova Drift will keep outputting to my headphones, unless I exit and restart the game.