Foam inserts in CD fatboys - a warning

I noticed on a couple of other forums recently that people were warning about the use of foam inserts in the old "fatboy" double CD cases. I bought most of my opera in the late 80s and early 90s and these foam inserts were prevalent back then. The foam degrades and disintegrates and will adhere to the surface of the CD. Having seen the warnings I checked my entire classical collection. I removed around 50 of them. Many were showing signs of disintegration and around 10 were bonding themselves to the CD. Now in all cases the surface was the uppermost one and not the playing surface but it's still damage. There is a sticky residue left on the disc and until I know how to clean it, I'll leave it alone.

So people - take a look at your old fatboys and check for these nasty inserts. Any ideas about cleaning would come in handy.
Yes I have had this issue.
The only solution is to discard the foam.. hopefully before it ruins the CD.
If the foam is adhering to the CD, the absolute BEST solvent to remove it is naphtha (what dry cleaners use.) It will not hurt the surface of the CD in any way. The easiest source for it is either Ronsonal or Scripto lighter fluid (ACE Hardware usually has Ronsonal).

Just dampen the foam, wait 30 sec. or so, and gently remove it. You can wash the CD afterwards with a mild solution of dish detergent, and rinse with dilute (50/50) white vinegar to get any detergent residue off.

DO NOT use products like Goo Gone! It will eat into the polycarbonate CD (and a lot of other plastics too; and polymer finishes like Varathane and spray lacquers). Naphtha is amazing stuff. You can use it, for instance, to clean vintage vacuum tubes, even the old Teles and Amperex with those fragile chalky labels, without fear of dissolving them (just wipe them gently with a tissue dampened with naphtha -- don't rub them, it's not necessary.) Whereas anything with just a HINT of water in it (even 90% alcohol) will take those labels right off!

I've been using it for years, and it has never ruined anything -- it simply softens adhesives, even old adhesive, like UPS labels you want to get off a box so you can reuse it. It's also great for cleaning. Especially cleaning surfaces just before you are going to apply anything with a self-adhesive backing.
Nsgarch, good stuff! Thanks for the info.