but when a business upscaled into a multi-national corp... and ships mfg overseas, you're going to increase the bad-apple count.
Case in point: K2 is producing 40 different consumer boards for 08/09 (even though they only list 28 on their website's front-end).
I would guess that this 'milky' look is a very dry and heavily oxidized (burnt) base screaming for wax.
P-tex only oxidizes at very high temperatures; temperatures unlikely to ever reach a snowboard during its lifetime.
Base Oxidation: Pulp Fiction
Over the years, the wax industry has perpetuated the notion of "base oxidation," claiming that base material in skis and snowboards made out of Ultra High Molecular Weight Polyethylene (UHMWPE) can oxidize over extended periods of time if left unwaxed. In addition, many well-respected books on ski tuning repeat the mantra that frequent waxing is important to avoid "base oxidation." As it turns out, "base oxidation" is total fiction. The P-Tex material in your snowboard is inert, and can't oxidize. If you ride your snowboard for an extended period of time without waxing it, grayish streaks will form on the base, but that's a result of abrasion, not oxidation. Yes, it's important to wax your snowboard as often as you can to protect your snowboard from abrasion, but "base oxidation" has nothing to do with it.
This revelation was provided courtesy of Jim Honerlaw, a chemical engineer at Crown Plastics, a manufacturer of UHMWPE for skis and snowboard bases. He explained that oxidation of UHMWPE only occurs when it is exposed to very high temperatures (> 270º F). One such high-temperature scenario can occur when UHMWPE is machined into shapes used for artificial joints, which means extra care must be taken during the machining process.
To recap: UHMWPE oxidation may be a problem in your artificial knee, but not in your snowboard.