Inconsistent hardware health monitoring results on Cisco Catalyst 3750 stacks

Hi,

After getting the runaround from support which is accusing Cisco (as usual), I would be interested in knowing if anybody else is experiencing "Hardware Health" monitoring issues on Cisco IOS devices while running NPM 11.

Here is one of our 3750 stacks health monitoring results, which is what we expect:

And here is a more problematic stack (however, it's configured in the exact same manner as the working one):

As you can see, the second one only shows results from the network modules instead of the switch itself. I have poked around for hours, removed/readded the stack to NPM but no dice.

Help please