Sara and Eva

Hi, I'm trying to midi sync 2 looopstations with each other. I want the phrases to tempo sync but can't get them to play together at the same tempo. We are two people who want to use the 6 channels at the same time. Imagine 3 loops recorded by 1 singer, and the other singer wanting to record an extra loop on another loopstation with the exact same length as the first 3 loops Its almost impossible toget them exactly at the same tempo when we do it manually. Thank you so much for your advice! Sara