Solved by Lachlan_Burne in post #2 
              
              
                Fixed my own problem. In case anyone else runs into the same issue, the problem was my custom dataset class. I mistakenly believed that python created copies of variables by default, e.g. 
a = [5, 5, 5], b = a  
would create two distinct variables, when in actuality b is simply a reference of a. Thi…