Hello @LeanderK - did you find what was causing this issue?
I am experiencing exploding gradients in a cascade  of 2 models where the first model W is unsupervised (which is training using this loss 6) and the second H is fully supervised using CE loss.
Are you using a similar setting because in your original post you mentioned: “predicted from another model”
Please let me know if you have found a solution to this.
Thanks,
Megh