Given that it hasn't been exposed to sunlight, I default to the idea that the wraps are partically affected by the adhesive used to bond them to the shells. There is also the possibility of some variation in the outer ply content, though I think modern Ludwig drums are supposed to have all maple shells now. At least that would be the case unless you are talking about secondary market drums made outside the US.

Pictures will help if you can upload some.

Have you tried to contact Ludwig on this? The drums have never been by a window?

pictures as mentioned would be a big help for us on the forum, If bought new and they are professional Ludwigs you have a warranty.

I must comment here as well, seeing as all I own play is WMP! With a wrap that is only four years old, that should NOT have happened even if the drums were in direct sunlight. WMP wrap is finally STABLE in shrink, fade, and sunlight damage, and has been for at least the past 5 years or so! Is it "possible" that the wrap you have might have been at the tail end of the unstable material? Possibly. Even so... Jeff and VM2K have the best thought: Contact Ludwig about it. I would think they would make it right.. if .. it is their problem. Pics will indeed help!

Tommyp

Haven't tried contacting Ludwig yet but here are pics.

Half the tom is yellow and third of Bass Drum.

Thanks

Wow ! I'll be very surprised if Ludwig makes it right .You have my sympathy , though . I don't think this would happen to a name brand drum made in China !