Are you sure you are not extruding too hot? That could also cause stringing.
How fast are you trying to print? Might be trying to push too much plastic.
When I first got my delta (over 2 years ago) I had a somewhat similar issue. I ended up replacing the heat break and it fixed it. I guess I had pulled molten plastic up into the PTFE tube and it was on there for good causing all kinds of weird issues like this.