No audio playback

I am using Scarlett 2i2 and Cubase LE 7. All was working fine when I unplugged the unit and went away for a few days, taking my laptop with me. When I returned home and plugged in again, I could no longer hear playback through the headphones. Playback was fine through the laptop speakers. Playback works in GarageBand. I did nothing to settings. I simply plugged in again and tried to pick up where I left off before I went away.

Headphones work. Second pair does too. 2i2 seems to be working fine. Just no audio playback in Cubase, as far as I can tell. And I’m no genius. So I could be missing something very simple. Help is much appreciated.