
Reader Glen Franklin has had it with AirPort Utility’s pestering. He writes:
I’ve read reports of the latest AirPort update (7.6) causing problems for some people so I’ve decided to avoid it until the next update comes along. The problem is that whenever I wake my Mac, AirPort Utility launches and reminds me about this update. Is there a Software Update setting I can adjust to keep this from happening?
In this case Software Update isn’t the culprit but rather AirPort Utility. By default, it’s configured so that whenever an AirPort Base Station displays a blinking yellow light, AirPort Utility launches and attempts to explain what’s going on. In your case, AirPort Utility is aware that you’re not running the latest firmware, which causes the blinking light, which, in turn, causes AirPort Utility to launch and display the message.

You can put an end to this by launching AirPort Utility, choosing Preferences from the AirPort Utility menu, and unchecking the Monitor AirPort Wireless Devices for Problems option. Do this and AirPort Utility will no longer automatically launch when the base station blinks yellow.
As for this firmware update, there have indeed been reports that it causes problems for some people. For that very reason I too have stuck with version 7.5.2. However, last week at Macworld|iWorld, I asked those who’d know how safe this update is. The general consensus was that it was perfectly fine. So, you might give it a go.
And you might because you can always switch back to version 7.5.2. To do so, launch AirPort Utility, select your AirPort device, and choose Base Station -> Upload Firmware. From the resulting sheet choose 7.5.2 from the Upload Version pop-up menu and click OK. Your device’s firmware will be reset to version 7.5.2.