Need help to play turntable through surround instead of stereo using a receiver

Hi,
This is my first post here. I couldn't find another thread on this topic so I thought I'd make a post. I have a Pioneer VSX-330 Receiver connected to a 5.1 surround setup. I have an audio technica turntable hooked up to a small stereo in-out amplifier then into my receiver. I've read the receiver's manual 4 times over and I still cant figure out how to output sound through all 5 speakers (and possibly the subwoofer?) and not just stereo through the two front facing speakers. Any help would be greatly appreciated!!
Cheers.