App that prevents sleep when lid is shut? (solved)

I'd like the ability to continue listening to a podcast after I've shut the lid on my rMB, just for those times I'm moving between rooms. In the past I've used Caffeine or Don't Sleep, but these appear not to work when the lid is shut (i.e. it sleeps and the audio stops). Can't remember if it worked this way in the past on previous mac's, but it definitely doesn't work this way now unfortunately.

Suggestions? Running El Cap btw.

EDIT: I've just remembered I used to use InsomniaX, will...

App that prevents sleep when lid is shut? (solved)