Since I first wrote about the MacBook Pro CPU noise problem, some things have come into sharper focus. Unfortunately, there is still no official fix (or even acknowledgment of a problem) from Apple for the CPU noise, but there are some interesting tidbits I’ve noticed on the Apple discussion forums and elsewhere:
- The “brightness-related” noise is a distinct and acknowledged defect. Apparently Apple has identified the humming/hissing noise many MBP owners experience as caused by a faulty “display inverter.” The noise is usually only present when the display is at less than full brightness, and goes away immediately at full brightness. It sounds like owners who are afflicted by this noise can get their laptop serviced under warranty. I will certainly do this as it’s distracting and a waste of battery to run at full brightness, but I’m waiting to see if any of the other issues might be fixable in the same service request.
- People believe in magic. There is widespread discussion about the fact that running a 3rd party “Mirror” widget alleviates the noise indefinitely, even after the widget is shut. People are so excited by this fix that they are going out of their way to come up with automated techniques for invoking and then quitting that widget. I can’t help but think that if the noise is stopped, something interesting is still going on. I assume that running the Widget configures the hardware in such a way that power is being consumed even after the widget is closed. I took a look at the Widget and observed that at its core is a standalone QuickTime movie that contains all the iSight integration. You can open the movie independently of the Dashboard (with QuickTime Player) and cause the noise to stop. However, when you close the movie from QT Player the noise resumes. I don’t believe there is a magic solution to this problem, since it seems so directly related to power consumption.
- There is a 3rd noise. A somewhat distracting noise, sort of like a lowing cow, occasionally emerges from the lower-rigth quadrant of my MBP. I haven’t heard this noise discussed much, but in my opinion it might as well be tossed into the defect list. It sounds like a false-starting motor, or something. I don’t know if it’s a fan that starts up and then decides it doesn’t need to, or if it’s the DVD drive trying to access a non-existant DVD. I would like this issue to enter the discussion, though.
- Some people, including Scott Stevenson, have noticed that plugging an external USB device into the MBP alleviates the noise. This isn’t convenient for me, but if you’ve got a USB flash drive around that happens to silence it – might not be such a bad way to buy your sanity.
- People are excited about Cryptonome. Since I shut down comments on the last MBP noise post, people have been emailing me furiously, concerned that they might miss out on the culmination of Cryptonome’s work. I’m excited to see what he comes up with, but I have also been warned that such manipulation of the MBP’s power management strategy might be dangerous. I’m sure the delay in Cryptonome’s releasing anything is because he’s carefully studying the impact such a tool would have, but I would be timid about running such a tool all the same.
- QuietMBP is still the best all-purpose workaround I know of for the CPU noise. I’ve updated the application to include a slider so users can precisely control the amount of CPU the program uses. This should satisfy the curiosity of those who worry I could be using less CPU to achieve the same goal, and it’s also fun to play with the slider to hear the difference in sound at various CPU utilization. Download QuietMBP 1.1.
I still anxiously await a public response to the CPU whine issue from Apple. It’s the single biggest downer about the MBP and it’s affecting a whole heck of a lot of people. I’m still getting hundreds of referrals a day from Apple discussion forums, and the popularity of that single entry’s URL is about to exceed the default entry URL for my blog as a whole.
Update: People are starting to record their MacBook Pro noises, and to be honest they are usually not representative of what it really feels like to be in a quiet room with the problem worming itself into your brain. But this post by Paul Turner includes an interesting analysis of the sound showing up in Logic (Apple’s own pro audio recording software) with no microphone plugged in. He observed that the subtle but insanity-inducing “CPU whine/twitter” actually shows up in a Logic recording even when it’s not audible through the speakers. Interesting, indeed. I feel really bad for Apple. I love Apple and I don’t want to see this machine turn into a complete audio lemon. I also don’t want to regret my purchase, since I’m interested in home recording myself. This is just one more downer for what is otherwise a great machine.