Reset your project and scene
MASTER SEND
On main level raise fader 1 to unity
Raise main master fader to an approriate level
EFFECT SEND
Click on button FX A
Raise pink channel fader 1 to unity
Raise pink FX A send master fader to unity
EFFECT RETURN
Go to Aux 1
Search and raise yellow FX A return fader (next to channel 16)
Now you should hear plenty of effect in Aux 1... If you want to hear effects in stereo, the aux mixes must be linked (1+2, 3+4, 5+6).