I know this sounds like a silly question, but do you have your halyards led to the correct winches?
The main halyard goes up the back side of the mast and comes down the front. Since the winches all wind clockwise, it should be led to the stbd winch, which will keep the line toward the front of the mast. Similarly for the jib halyard, with the sides reversed
Although it will work with the winches reversed, it would cause the halyards to drag over the spreaders.
But more likely, your source of chafe is the wind causing the halyards to oscillate and bang against the spreaders and mast. My old wire/rope halyards had scraped the mast to an ugly mess, and chewed up the edges of the spreaders. When I rebuilt the mast, I had to have the spreaders repaired and had everything repainted with Awlgrip. I also went to all-rope halyards. When not sailing, I tie off both ends of the main halyard to the rail, at the base of two stanchions, to keep it completely away from the mast, avoiding both chafe and that annoying slap. I also ease off the tension on the furled jib, and move it's halyard from the winch to the rail.
