I’m writing to bump this thread.
I gave up on PyTorch a while back, and went back to Keras because of these issues and the lack of actual resolution in the forum on this.
But I’m interested in trying PyTorch again.
I notice that there’s now an official PyTorch/example for Time Sequence Prediction (https://github.com/pytorch/examples/tree/master/time_sequence_prediction 32), and was happy to try it out, but it just produces the same output as we described above, namely it just dives for a fixed point and stays there (screenshot of predict14.pdf):

predict14.jpg2160×720 61.5 KB

Can someone comment on this?  It’s odd when even the example code doesn’t work.