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N9912A FieldFox dead pixels: Hardware failure or firmware bug?

Question asked by swperk on Aug 12, 2012
Latest reply on Aug 17, 2012 by swperk
I just installed the latest firmware (A.06.02) on my N9912A. I was observing a spectrogram display and noticed something that may represent a hardware failure. I saw a block of eight pixels (4 wide by 2 high) in the lower right corner of the display that were always black. I had never noticed this before, and saw it right away after the firmware upgrade, so I'm pretty sure it just recently happened.
After an hour or so of playing around with the CAT, NA, and SA modes, I find that the pixels are "dead" in all those situations where there is a sweep speed label in the display, and the dead pixels are always in exactly the same position relative to the sweep speed label: about 1.25 cm above the baseline of the label, and inset about 2.5 mm from the right edge of the display. Even in the "split screen" spectrogram display, the dead pixels always follow the sweep speed label.
I've attached three screen shots that illustrate these observations, the third one showing no dead pixels in the full screen mode (when there is no sweep speed label on the display). Apologies for the moiré patterns, but you'll get the idea.

So is this a display memory failure or a firmware bug? I haven't tried downgrading back to A.05.53 to see if the problem follows, but that may be the next step.