We had a similar problem with Jake--he was constantly scratching, and had very dry skin. He's on Eagle Pack, so I don't think the food was his problem. I got some capsules through my SIL who is a vet--they are by Allerderm and are EFA-CAPS HP. I just squeeze the gel out of one on his supper every night, and the scratching is pretty much gone. His coat was nice before, but now it is beautiful! They are a bit pricey, though.
I've seen a picture of Jake and he is gorgous. Ask Andrew to post a picture of him here we would love to see him.