I had been playing video via HDMI out, and now I've disconnected it, but chrome is still sending the audio to the HDMI device. How can I change it?
Control Panel -> Hardware and Sound -> Sound.
Your audio devices are listed there, and the HDMI device has been set to default when you plugged the HDMI device in.
Change the your standard output to the default.
Now restart chrome, and it should work.