PXI chassis flashing red, but voltages are good: ideas?

[uiop]

The power switch on my PXI 1045 chassis is flashing red.  It is a repeating pattern of 3 flashes over 3 seconds, followed by 3 seconds of dark.

Yes, I know that it indicates an out of spec voltage, but the voltages at the Db9 on the back of the chassis are fine according to  the NI PXI-1045 User Manual (pages 2-8, 9, 10, table 2-2).  The +3.3V measurement is slightly over the upper spec, by 0.03v.  Distortion at any of the monitor points is abut 200mV

I have other racks that are more out of tolerance than that (0.12v over), and have more distortion (up to 300mv) and they do not have this issue (flashing red power switch)

The rack is cool now and totally empty, but the flashing persists.

Anyone have a clue what else may be wrong?

[uiop]

Should anyone search this in ages to come, this is where the issue went:

1) Unloaded the chassis (removed all the PXI cards):  no change, switch is still flashing red.

2) Cooled the chassis for 6 hr:  no change, switch is still flashing red.

3) Removed, and then re-inserted the chassis power suppy ("power supply and shuttle unit"):  switch stays green after power-up

4) Re-install all PXI cards (MUXs, DAQs, controller, power supply, RFSA, downconverter, DMM, and more), and power-up for 3 days:  switch stays green.

I wil re-install this loaded chassis into the system from which it was removed.  If this tanks again, I'll update the post.  If not, consider the issue "over".

[zAep]

Just has same problem. Removing and reseating the power supply shuttle worked.

[uiop]

Yup, the fix (reseat) has "stuck".  Couple years now and still OK.