I was wondering if someone could please explain why some CM-series Roland boxes get yellow over time, but others are relatively if not completely immune to yellowing?
Only 2 CM-series boxes I have of several in my collection thus far (I recently acquired some new ones), have absolutely no yellowing whatsoever. The first one I have had since 2005 and although it doesn't have any yellowing, it does have some scratches. The second one I have which I relatively recently obtained has no yellowing at all, no scratches, and is also in practically brand-new / mint condition.
But the others -- they range in condition from some yellowing, to extreme yellowing, to almost looking light brown and/or coffee color. What I'm wondering here is, why is the very first CM box i obtained in 2005 still have no yellowing at all, to this day, while the others are yellowed considerably? Almost all of the online sales I have noticed recently, counting both e-bay and others sites, have CM-series boxes with mild to moderate to severe yellowing. I have actually gotten burned before because the yellowing wasn't always noticeable in the auction pictures, and I only found out after the fact, when they had been already shipped to me.