Solved by ragnaarok in post #2 
              
              
                Ok, using 
torchvision.set_video_backend('video_reader') 
solved my issue for the “sec” unit. I now have [251, …], [2, 441344]. 
And the “pts” unit seems to be depreciated so it’s not important. 
Seems to be solved. 
Though it says in the documentation I should compile torchvision from source but I …