Sound "plops"

[longtom]

Sometimes there is a little "plop" berfore the sound.
Some others having the same issue?

 

[longtom]

Yes, when cahanged to MacPro3,1 then it's fine.

 

[cbooty]

Been looking for a solution to the sound "plop" for some time - changed my smbios.plist to MacPro3,1 and low and behold problem fixed. No idea why simply changing from iMac to MacPro would work but very glad it does

 

[themac]

Hi cbooty/longtom,

I too suffer from "the plop" so would like to try this fix.

Could you please share your smbios.plist or explain what needs changing? I have searched but struggled to find anything that helps me understand this issue.

I am using Tony's smbios.plist which he included in his Restart Tweak guide.

Many thanks.

<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE plist PUBLIC "-//Apple//DTD PLIST 1.0//EN" "http://www.apple.com/DTDs/PropertyList-1.0.dtd">
<plist version="1.0">
<dict>
<key>SMbiosvendor</key>
<string>Apple Inc.</string>
<key>SMbiosversion</key>
<string>IM111.88Z.0034.B00.0910301727</string>
<key>SMbiosdate</key>
<string>11/06/2009</string>
<key>SMboardmanufacturer</key>
<string>Apple Computer, Inc.</string>
<key>SMboardproduct</key>
<string>Mac-F2268DAE</string>
<key>SMfamily</key>
<string>iMac</string>
<key>SMmanufacturer</key>
<string>Apple Inc.</string>
<key>SMproductname</key>
<string>iMac11,1</string>
<key>SMserial</key>
<string>W88033AKY51</string>
<key>SMsystemversion</key>
<string>1.0</string>
<key>SMUUID</key>
<string>C0CE2600-93D7-3B41-843A-4D7C8E2C12E2</string>
</dict>
</plist>

 

[cbooty]

Hey themac:

As far as editing the smbios.plist its really straightforward, I've entered the edits for your plist below. Paste, save, reboot and you should be good to go

<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE plist PUBLIC "-//Apple//DTD PLIST 1.0//EN" "http://www.apple.com/DTDs/PropertyList-1.0.dtd">
<plist version="1.0">
<dict>
<key>SMbiosvendor</key>
<string>Apple Inc.</string>
<key>SMbiosversion</key>
<string>IM111.88Z.0034.B00.0910301727</string>
<key>SMbiosdate</key>
<string>11/06/2009</string>
<key>SMboardmanufacturer</key>
<string>Apple Computer, Inc.</string>
<key>SMboardproduct</key>
<string>Mac-F2268DAE</string>
<key>SMfamily</key>
<string>Mac Pro</string>
<key>SMmanufacturer</key>
<string>Apple Inc.</string>
<key>SMproductname</key>
<string>MacPro3,1</string>
<key>SMserial</key>
<string>W88033AKY51</string>
<key>SMsystemversion</key>
<string>1.0</string>
<key>SMUUID</key>
<string>C0CE2600-93D7-3B41-843A-4D7C8E2C12E2</string>
</dict>
</plist>

Cheers,

Christian

 

[themac]

Cbooty many thanks - worked perfectly.

For anyone else wanting to try this out, there are only two changes:

1 - iMac to Mac Pro
Original:
<key>SMfamily</key>
<string>iMac</string>
Updated:
<key>SMfamily</key>
<string>Mac Pro</string>

2 - iMac11,1 to MacPro3,1
Original:
<key>SMproductname</key>
<string>iMac11,1</string>
Updated:
<key>SMproductname</key>
<string>MacPro3,1</string>

Note: I still get a very quite plop during startup and quite a loud one on return from sleep but now no plops when playing sound for the first time during normal use or after some time which is definitely a worthwhile improvement for me.

 

[wlp5]

Weird, I have the same MB/CPU and have not experienced this plop sound ? Can someone describe it better ? Is it by any chance the Apple "plop" sound when changing the volume through keyboard? or the sound labeled "pop" in sound effects preferences section?

 

[cbooty]

The "plop" as it is being referred to is definitely not the sound to indicate a change in volume but rather a sound that seems to be generated when the sound is initialized, typically during the boot sequence. The problem I was having was that the sound seemed to be turning on and then back off again with sound activity with an accompanying "plop" each time - rather annoying. For instance "plop" alert sound then "plop" again not long afterwards. And the volume of this sound could vary too seemingly. This change in the smbios.plist fixes the problem.

I actually had a very similar sound with my mac mini when it first booted but never during operation. So I think a "plop" sound during boot or after wakeup from sleep is "normal".

One last thing, I have some very sensitive M-Audio speakers which I think are more prone to reproducing this anomaly and perhaps at slightly higher volumes.

 

[wlp5]

Funny, I have M-Audio speakers too (AV40) yet never heard this sound. I guess my question was, is it a system sound ? a file being played or is it a weird sound that plays accidentally.

If it is a system sound, perhaps a workaround would be to find the file and delete it or replace it by a silent file.

 

[themac]

Definitely not a system sound - for me at least - more like the sound you get when you switch a cheap amplifier on or off (capacitive discharge?). BTW I've just got a cheap pair of amplified speakers (Labtec) plugged into the green socket on the back of my system unit.

I'm delighted that the Mac Pro fix identified by longtom works but have no idea why. Interestingly (or not!) my late 2007 MacBook does exactly the same thing when connected to the same speakers. The only answer I had ever found to this was that it was a hardware issue with the MacBook although I was never convinced of this as there was no such behaviour when running Vista from boot camp. I have Windows 7 installed on a separate disk on my Hack so will run a few tests and edit this post with the outcome.

Edit: With Windows 7 a very quite plop during startup (like OSX) just before the GUI starts but that's all so I'm convinced it's not a hardware issue.