TS,
I dun use CPC2, but from my experience prematurely spoilt rubbers r usually:
- poor maintenance (under/over inflated, constant curbing, or harsh usage)
- tyre structure even when fairly new. eg. there's plenty of feeback on rather thin/soft tyre walls on some Falken tires although it could b a form of NVH supression feature.
- lemon units regardless of brand n model. N if ur lucky ur supplier/tire shop or SC may replace it FOC or wit a minimal fee.

But ur set seems to be rather new. Perhaps other CPC2 users can contribute?