I've been using Duncan Hines mixes for 25 years. I just recently began having a problem with some of my cakes falling apart--literally crumbling into pieces shortly after icing them. I haven't changed my icing recipe or the way I bake the cakes. Has anyone else ever had this problem?
hhhmmmmmm I noticed this today too but I thought I was crazy, I wonder if it is the rainy weather for me, or if it was because I was making a PB cake and added PB???
i recently went to the Duncan Hines website to find if they made a particular flavor and i read in the website they if you are making more then one mix or making a tiered cake to adjust some of the ingredients, i don't know if this applies to you but you might want to check.
seems like from reading the threads there have been headaches with Duncan Heinz lately; I used one today and it fell in the middle.... 
Seems like a lot of people are having that problem, disappointing....
You might want to go to this thread... it's a repeat...
http://forum.cakecentral.com/cake-decorating-ftopic-339293-0.html
I know there have been post about others having problems with the new DH recipe.
But as for your buttercream recipe does it call for crisco? Since the crisco changed to the zero transfat it has played havoc with my icing recipe, but I know it hasn't effected some people.
Just a few other things to think about.
I just made a wedding and groom's cake yesterday..My largest layer was a 16" and I marbled it with DH classic vanilla and devil's food and had no problems...I wonder why I have seen no change..very strange. I'm sorry for those of you who are haveing trouble. I hate taking the time to bake a cake and then have it fall apart 
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