bencr:

I based the script on the LunaTrainingApp from “Deep learning in PyTorch” by Stevens as I found the script to be elegant. Of course I modified it to match my problem.


It’s a good idea to reuse a well written script 
I cannot find any obvious issues in your code, so could you try to overfit a small dataset (e.g. just 10 samples) and see, if your model and current training script is able to do so?
Once this is done, you could try to scale up the use case again.