Hi, i got my 4003 from ebay in england. When the neck is dead straight and i press behind the first fret, the string rattles like hell. But when i press the second fret the buz is totally gone. I only have this problem with the E and A string. I tried different strings and all but the problem remains the same. Did I buy a faulty ric?
Could be a high fret, could be a low nut, could be the bridge. Try raising the bridge a wee bit on the A/E side first, just need a small allen wrench and takes just a nanosecond and it may be enough to fix it that easy. But if that doesn't help, I'd see a luthier about the fret level.