I think you're confusing people, you'll need to state which fans (front or rear), not just say whatever comes on when charging, that the noise is coming from. If you're now saying the rear of the car is where the noise is loudest and has become louder than before, than that's the rear blower. But I'm starting to thing this might be subjective now. Just saying, you need to quantify what your problem is so people are not just sling-shotting random ideas back and forth which does not help anyone.
By the way, the rear blowers are extremely loud on the 2.x when charging. When I borrowed a 2.0 that thing was obnoxiously loud! I think my neighbors would complain if I made that type of noise everyday.... My 1.5 is rather quiet and happy it stays that way. The rear blowers don't need to run while charging, only the front fans. The 2.x sends air from the noisly blower up into the PEM, the 1.5 does not, it has its own on-board fan that's rather silent.