No sound in sample editor

I’m new to cubase so this is probably a stupid question, but how do I get sound is sample editor? I have sound when I play back the main project using the transport but get no sound when I try to play back a sample in sample editor. I have double checked and the audition volume in sample editor is set to max but I’m not sure what else to look at. If it is relevant I’m using a motu ultralite mk3 hybrid and and I’m running windows 10 64 bit.