Eclectic Memes

Okay, this one took a few minutes to nail down.

For a while now, my MacBook Pro would suddenly announce I had requested a shut down by displaying the ‘Are you sure?’ dialog. This would be fine, if I had actually asked the damn thing to shut down.

This was just a minor irritation at first and I assumed I had knocked the shut down key on my keyboard (even though it is recessed – who knows, I may have been clumsy).

Anyway, this shut down prompt suddenly became very insistent yesterday. Every time I dismissed it it would reappear after a random time, sometimes immediately sometimes after a few seconds, but frequently enough to be very obstructive. Yesterday it seemed to stop after I closed down Safari and restarted the machine. For the rest of the day the system behaved impeccably. Why this should be I have no idea.

Anyway, today it became very insistent again. So much so that the machine was all but unusable this morning. Arse and double arse!

First suspect – low battery in the external wireless keyboard. Perhaps a low battery causes the keyboard to send odd signals? I see no reason it should and the keyboard battery indicator was not lit, but eliminating the easy things first is generally a good idea. Replace batteries. Problem persists. Unplug keyboard completely and use built in keyboard. Problem persists.

Next suspect – new USB hub which was added to system a few days ago. Unplug USB hub. Problem persists. Hmm!

Right, unplug all external devices. Ah ha! Problem goes away. Naked laptop works just fine.

Okay, add external screen back. Problem returns!

The 30" Apple Cinema HD monitor I use seems to be sending shutdown request to the machine. The monitor certainly has a power button on the side (one of those touch sensitive switches) and is certainly capable of telling the system to which it is attached to power down.

Now, the problem is, has the monitor developed a defect (in which case Apple can repair it under warranty) or has one of the recent updates to the OS caused it to behave this way? Or is there something in the environment that is causing the monitor to think the power key is pressed?

A quick dig into the monitor preferences reveals an option to ignore the power switch completely. Setting the preference to completely ignore the monitor power switch has solved the immediate problem and means I can once again use my system – hurrah!

I never use the power key on the monitor, so its loss is no big deal. I will have to take the monitor in to the local store and have them test it some time in the next couple of years (before the AppleCare program runs out) but for now the monitor itself is working fine so I’m not inclined to go through the pain of unplugging it all, boxing it and dragging myself to the Apple store (this monitor weight about 12kg and I know from when I bought it, it takes a fair bit of effort to lug around a shopping centre).