My MacBook's internal microphone input level is too low since update

Ok try this for a very temporary fix, I thought the mic might be loose so I was messing about tapping the mic area to see if it would help but I found this out...

Try holding your thumb over the mic when your mac starts up or comes out of standby (it's the small left hole next to the camera) so your trying to block as much sound going in as possible.

Now, go to the prefs and see if you have sound input.

It works on mine nearly every time - but it only lasts a few minuets at most. It don't work too well after a short standby, but after 5-10 min it seems ok.

I'm now convinced it is software for sure, my line-in and USB mic works fine (for a short time ) when I do this. What I think is happening is it is doing some sort of background noise reduction, and doing it too well. By blocking out any initial sound it works for a while until it readjusts - mine lasts a few minutes at the most.

I can't downgrade to 10.4.6 as my mac came with 10.4.8 - but it did work initially so maybe it is one of the other extra updates it downloaded. Maybe, those upgrading to 10.4.8 get the extra updates with the os update.

Hopefully ill get a chance to do a clean install over the weekend, then ill check the mic between every update it downloads.

Just wondering if anyone has any updates on this yet?

I've still not had chance to get to an apple store, but just updated to 10.4.9 and still having the same problem. Has anyone taken it in yet & got a fix that does not require a re-install?

Ant

Just wondering if anyone has tried the 10.4.9 update yet to see if it alters our problem?
I have to do a massive backup before I try any update. Just need the time.

Yeah I am wondering if the new update fixes the beeping problem as when I turn on the camera in imovie the first time for of that particular boot.

Nope, 10.4.9 did not fix it. I've rang apple care again and they still have no knowledge of a specific problem (just tell me to do the usual pram/verify checks or bring it into a store which I can't easily get to) - I would have thought with the number of posts about it they would have at least checked it out.

10.4.7 did not have this problem? Is it safe to try to install 10.4.7 to try and fix this microphone problem? I am running 10.4.9 and had 10.4.8 before and I would get this horrific loud beep from my imput volmume being too high for isight in imovie.

Hi everyone,

After seeing all the issues you were having with your input level in iMovie and the like, I took it upon myself to try it too. When I first tried iMovie to record myself, I played it back and was confused that it was doing as you all were talking about. It had always worked before, of course I did have to always check for the input level before recording, just to make sure.

Then I went into System Preferences and checked some stuff out. I tried looking in "Speech" and found that you can calibrate your "Internal Microphone". I did that and now all is well.

So try calibrating your internal microphone and get back to us all.

I may have just gotten lucky, but when I consider mine was working and then wasn't, this might be helpful to some of you.

I hope this helps some of you.

Adam

No, it didn't help - it looks like the speech calibration bar just adjusts the input volume the same as the one in sound prefs.

It was working for maybe a minute or two after I first switch on or it comes out of sleep - but as usual after the that it just stops.

Just got my macbook back from applecare. symptoms = nearly deaf, flaky thermometer readings on input sound preference panel. especially weird was that the thermometer would jump wildly when the screen was creaked back and forward slightly.

applecare replaced the microphone assembly, the heat sink assembly and THE MOTHERBOARD!

something is going on here.

jugface