tantrum

Hi guys I'm needing some help. I've had to reinstall my standard head unit and now I have no sound. Everything works but no sound. I have plugged everything back in as original as far as i can tell. I have a pioneer harness piggy backed to the original harness so if i needed to put the original unit back in it would be easy. Please help. I have a 2012 xb in Australia. Toyota double din head deck with sat navigation etc.