I have a setup where I'm directly feeding a second recycler right from the output of a scrap recycler. After running it for a good while I haven't seen a single piece of wood from electric poles or wooden chests in the output.

Apparently whenever a recycler backs up, the random item logic can fail if it tries to become anything that isn't allowed in the recycler output, which is anything that isn't the result of a normal recycling recipe. It wasn't just chests and poles, it was every entity that isn't used in a recipe, e.g. burner inserters, steam engines, etc.

When pointing a recycler at another recycler, because the dummy item the recipe produces doesn't have a recycling recipe, the item always ends up in the recycler output and thus never becomes any of those things.

I'm not sure how this bug wasn't noticed until now, but I've fixed it for 0.0.8, thanks for the report