XR18 - No audio signal going in



I bought a new XR18 to replace me XR16.

I connected it to my Mac and loaded all my saved snapshots to the XR18. I also updated the firmware.

When I turn the mixer on and connect my microphone an piano, no sound goes in the mixer. Nothing. I tried initializing but it didn't help.

Anyone with the sme issues? How do I fix this?