The opposite of listening to Spanish while reading English is to listen to English while reading in Spanish. And Stephen Fry does a good job!
At first this will feel weird. It too feels as if nothing is being achieved. And yet it serves to link understanding to Spanish. It makes the input comprehensible. Mirror-repeating this and the previous step for the same passage of text cannot but help with acquisition.
I used to find this arrangement more difficult than the reverse. I’d need to pause after every sentence. But I have no problems now and can just smoothly continue.