Gameplay Sound Not Recording

[AndyCr15]

I wonder if someone can help. It's probably something very simple, but I can't see what...

When I record video of me playing a game, I'm getting my voice through the mic, but none of the games sounds. I have 'Record system sounds' selected. If, while recording, I come out and select 'Test' on my speakers (the chosen system sounds in Action! settings) it will record the pinging noises the speakers make... but not the sound from the game I'm playing.

What have I done wrong?

Thanks.

[AndyCr15]

I think I've sorted it... I have to have system sounds up at around 75%. I think it's then from the gameplay rather than the mic. Does that sound right?