The mystery remains

I have been thinking a lot about what on earth could have been the cause of the fabric disintegration on these two pillow cases.
* I sew five different ones during the same time frame.
* As far as I can remember, I used the same thread on all of them.
* The inner pillows on all of them differs
* Once of the cases are made from a FQ bundle containing among others these fabrics:

Most selvages are gone, but on the few remaining it say "Antique Flower collection printed by Lecien", but I doubt very much that all fabrics are from the same collection of the same producer since they feel very different to the touch
*When you look at the pillowcase made from a lot of fabrics like these above, you see that only some fabrics are affected, which rule out the ideas that it can be the batting or the inner pillows or the thread or  the xxxx that is the culprit.... Heck, I do wish it was the Guterman thread I used back then would be the cause, because then I would knew for certain that all latter projects will be safe, since I never use these threads for quilting any more.
* Maybe it's the house mouse Coffee that had a field day before he was captured by Sam? He sure loves fabrics and batting and Sam has got a small stash of left overs to use in Coffess little Hobit house. Or maybe it was the dogs when they was false preggers? Nahhh, how come some fabrics are unaffected then?

On a sidenote - I used a lot Mayflower Muslin from Benartex in my MIL's DWR quilt and some of the melon wedges kind of kid brittle, crackled and fell apart from ironing. Have no clue why, but it might have been that just that fabric was very very sensitive to heat...(or the stupid Tefal iron went highwire), but not all of it since most wedges stayed intact. Maybe it's just me?? The fabric shredder;-P Nahh, I have made quite a few items that by now are around 3-3.5yrs and they are just fine. So far.....

The spring has sprung and my miracle music thingee has started to behave very strange. It does not go to the next tune, but repeat the last played one over and over again. I have read the manual, restarted both the pod and the computer to no avail. .......heavy sigh.

Edited: read some more on Apple website and rebooted the pod and low and behold - now it works like a charm again. Women can too!!! ROFLMAO. Now I don't have to listen to John and his friend Erik playing PS3 just outside my room:-D