MacBook Pro audio suddenly tinny, no startup bong

[maknik]

I have a late-2009 15" MacBook Pro running 10.6.8. Sometimes I use it for white noise when traveling, but last night when I was using it suddenly all the lower tones disappeared and the sound got very tinny. When I play videos or music, it also sounds faint and tinny. When I use headphones, it sounds fine. And when the computer restarts, there is no bong sound, even though it is not muted when I shut it down.

The most fundamental questions is whether this is a hardware or software problem. It still plays sound, in stereo, so neither of the speakers has burnt out. Is there a separate woofer that might have gone bad?

If it's software, I've tried zapping the PRAM and doing a SMC reset. I've thrown out sound preference files in ~/Library/preferences/audio/ and ~/Library/Preferences/com.apple.systemsound.plist and restarted. I've checked the sound preferences for anything odd, but it all looks the same as ever, and I've tried changing settings in the Audio MIDI setup, to no avail. I was running Audio Hijack at the time (to make the white noise pinker), so I tried removing that, but no effect either. I even tried reinstalling the 10.6.8 combo update, but no effect there either.

Any thoughts or suggestions from anyone? It's a real pain, since not only is the white noise now far too hissy, but more importantly the speaker sound is now too faint and tinny to watch videos or listen to anything without headphones. Help!

 

[CaffeinatedNoms]

If you're incredibly lucky, it might just be a bad connection. If you feel confident enough, open her up and follow the black cables that run between the speakers and the motherboard, and check they're all firmly seated on their push-click things. If they're not, like the name suggests, push and click them back.

If it's not that, then it sounds like the actual drivers have shorted and died. You can try replacing them but I've never done it myself so I can't vouch for how easy that may be.

 

[maknik]

Interesting idea -- I'll give it a shot when I get home. I'm not afraid to crack it open, having replaced the hard drive and battery over the years (though the last one was a while ago, so I doubt that was the cause of this). But is there a way that the connection could go that knocks out the low tones but not the high ones? Or if it's the drivers, can something die that only knocks out the bass or higher volumes?

 

[CaffeinatedNoms]

If it was only the bass, then it would be logical that only the subwoofer driver had died, but if it's affecting the volume for both right and left speakers (only the right side has a subwoofer) then I think something else may be afoot.

I found these guides, which should help identify the cables to check:
Right Speaker and Left Speaker

 

[maknik]

Yikes -- that's a lot of steps. Compared to that, even trying to update the OS to Mavericks seems easier, even though it seems more likely a hardware than software problem.

Do you (or anyone) have a theory why the startup bong would have stopped though? That's the only thing that gives me some hope that it's software...

 

[CaffeinatedNoms]

You can try flashing the NVRAM; hold down Cmd+Opt+P+R as the Mac starts, and keep them held down until the Mac starts a second time. That often helps unstick software issues

 

[DeltaMac]

The startup boot chime is NOT produced by software (though it can be muted or affected by your software, you should still be able to hear the boot chime after a good PRAM reset, regardless of the condition of your software)
"Sounds" like your subwoofer has failed.
I'm not sure why that would leave you with no boot chime, so that would make me suspicious of the sound chip on the logic board.

Try a more lengthy PRAM reset - that is, restart while holding Option-Command-P and R. You may hear a "reset" of the CD drive at about the same time that you would hear the boot chime. Continue to hold the same 4 keys until you hear the reset 2 more times, at least. If nothing noticeable happens, just continue to hold those 4 keys for 1-2 minutes, which should be long enough. Release the keys, and let your MacBook Pro startup normally.

 

[maknik]

Yep, as per the original post, I did try the PRAM/NVRAM reset. For good measure, I tried it again, letting it restart at least 20 or so times. No sound at any point.

It seems based on that that it is a hardware issue. But what's odd is that the tinny stereo sound still works. Perhaps that means the startup chime is sent only to the subwoofer?

 

[DeltaMac]

... No sound at any point.
…
.. But what's odd is that the tinny stereo sound still works. Perhaps that means the startup chime is sent only to the subwoofer?

I've never tested a boot without the subwoofer attached.
When working normally, if you restart with headphones connected, the boot chime does NOT sound through the headphones, but sounds through the internal speaker, even though the headphones are attached.
So, it seems likely that the boot chime sounds only through the subwoofer (I don't have any way to prove that)
Anyway, the only way to get your white noise back, is to replace the subwoofer. Be sure to check inside to make sure the subwoofer is properly connected.

I wonder if someone who knows more about audio than I - if the long-term use of white noise might damage your speaker?

 

[maknik]

I've ordered a replacement right speaker/subwoofer; I'll check back in with a report when I've installed it. I suspect the problem was not the white noise per se, but the fact that Audio Hijack allows you too boost the audio a bit, which means the speaker may have been overdriven whenever I was running the white noise generator. That was only a few nights a month, usually, but the white noise + audio boost seems like a plausible culprit -- if indeed it is a hardware issue.

 

[kevvjj9]

was there a solution to this problem? I have the same issue.

 

[DeltaMac]

If you get only tinny sounds from the internal speakers, then the subwoofer may have failed, as may have happened in to the OP.

Do you get any audio when you plug in headphones?
Did you try the PRAM reset? Do you get boot chimes when you try a PRAM reset, and hold the keys for about 30 seconds or longer?

 

[kevvjj9]

Yes to all. Tried everything, just want to know if replacing the right hand speaker/woofer assembly fixed the issue or not.

 

[donronbon]

(How) did you guys fix the issue? I have the same problem ...

 

[DeltaMac]

(How) did you guys fix the issue? I have the same problem ...

Which MacBook Pro do you have?
When did you first notice the problem?

What have you tried so far?
Did you try the PRAM reset? Be sure to hold the same 4 keys until you hear the startup chime two or more times.
If your sound is working, but tinny, then the subwoofer can certainly fail.

 

[kevvjj9]

(How) did you guys fix the issue? I have the same problem ...

I have a Macbook 13" Early 2011. I have the same symptoms as above. Stereo sound lovely throughout headphones. No startup chime. replaced all the speakers... no change. It's a logic board issue - need replacement logic board. So, my solution was to buy a small Bluetooth speaker and have it next to my laptop. Sound is great and I can live without the startup chime.

 

[Javy]

I have a 2010 Macbook pro, have been researching this issue for years now! I have the identical problems described in this thread and have tried everything including individually killing processes. only thing I didnt do is replace hardware.
I do know that there is no issue with the hardware because I installed Windows through Bootcamp and BINGO! full spectrum sound was back.

This issues is definitely software realated, just don't know what software did this

 

[amgff84]

I have a late-2009 15" MacBook Pro running 10.6.8. Sometimes I use it for white noise when traveling, but last night when I was using it suddenly all the lower tones disappeared and the sound got very tinny. When I play videos or music, it also sounds faint and tinny. When I use headphones, it sounds fine. And when the computer restarts, there is no bong sound, even though it is not muted when I shut it down.

The most fundamental questions is whether this is a hardware or software problem. It still plays sound, in stereo, so neither of the speakers has burnt out. Is there a separate woofer that might have gone bad?

If it's software, I've tried zapping the PRAM and doing a SMC reset. I've thrown out sound preference files in ~/Library/preferences/audio/ and ~/Library/Preferences/com.apple.systemsound.plist and restarted. I've checked the sound preferences for anything odd, but it all looks the same as ever, and I've tried changing settings in the Audio MIDI setup, to no avail. I was running Audio Hijack at the time (to make the white noise pinker), so I tried removing that, but no effect either. I even tried reinstalling the 10.6.8 combo update, but no effect there either.

Any thoughts or suggestions from anyone? It's a real pain, since not only is the white noise now far too hissy, but more importantly the speaker sound is now too faint and tinny to watch videos or listen to anything without headphones. Help!

So for me, on my two-two MacBook project, I lost chime and have tinny speakers after putting a logic board in a machine that it doesn't normally fit in. I left the sub disconnected as this logic board had no connection for it. No chime and tinny speakers are the result. This leads me to believe that the chime is done through the sub. Hopefully this helps someone, somewhere. You can check that Mac out here.

 

[Alberto Da Silva Pereira]

Dear all,

I ended up on this thread after seeking on Google for the same issue that I was facing on a MacBook Pro A1278 2011: tinny speakers and no subwoofer. No boot chime, no boot beep codes if no memory fitted on purpose, etc.

I tried Bootcamp, Windows sound options, etc. mentioned on this thread unsuccessfully so I sent my board to repair.

The tech pointed out to be a common issue with either component U6610, U6620 or U6630. He mentioned that they are normally glued to the pcb with some epoxy or so made glue because they tend to pop out of the pads. He even sent me some schematics and pictures that I'd like to share with you may you end up on this thread too using Google.

After resoldering U6620 on its place, the full spectrum sound is working again.

I hope that my experience may help others and save you time and efforts if you happen to have to troubleshoot this same issue.

Best regards,

Alberto.