Bizarre audio issue; can't figure it out for the life of me

[noamrrue]

2018 13" Macbook Pro running Catalina.

When I use my headphones, I hear a crackling noise, and it also is heard through the microphone (so if I'm on a call, others hear the crackling noise as well).

I have tried using other headphones. Here's the bizarre part though: even when I plug the headphones into a 3.5 mm-to-USB-C adaptor dongle, the issue persists. But when I use USB-A headphones plugged into a USB-C adaptor, there is no issue.

So there appears to be something about using 3.5 mm (aux/headphone jack) input, regardless of whether or not it's through the laptop's headphone input or through USB-C, that causes this issue. I can't for the life of me figure out why this would be the case. And again, I've tried using other headphones with 3.5mm inputs and the issue persists.

Any suggestions would be greatly appreciated!

 

[geejay9876]

Perhaps static electricity. You could try shoes with leather soles or naked feet and wear natural fibers.

 

[BrianBaughn]

Since your sound has no issues via USB it would seem that your MBP has something wrong with the 3.5mm jack or the module that controls it. Software issue? Maybe.

Lots of crackling speaker reports. I haven't seen any regarding a jack-only issue.

 

[rpmurray]

Do you have another pair of headphones with a 3.5 mm jack to try to see if the same occurs with them? You may want to check the cable, especially the ends on the jack and where they enter the headphones. If they got damaged or frayed then that would be the problem.

 

[Allyance]

It could be jack's solder joints on the motherboard have cracked and making intermittent contact. Saw alot of this type of damage on power jacks due constant flexing. Since other headphones have the same problem, I suspect solder joint damage. Gently wiggle plug while in jack and see if you can make it happen.

 

[noamrrue]

Do you have another pair of headphones with a 3.5 mm jack to try to see if the same occurs with them? You may want to check the cable, especially the ends on the jack and where they enter the headphones. If they got damaged or frayed then that would be the problem.

Yes, I had already tried a different pair of headphones unfortunately.

It could be jack's solder joints on the motherboard have cracked and making intermittent contact. Saw alot of this type of damage on power jacks due constant flexing. Since other headphones have the same problem, I suspect solder joint damage. Gently wiggle plug while in jack and see if you can make it happen.

Since your sound has no issues via USB it would seem that your MBP has something wrong with the 3.5mm jack or the module that controls it. Software issue? Maybe.

Lots of crackling speaker reports. I haven't seen any regarding a jack-only issue.

The problem can't be with the jack itself because the same issue happens I use an adapter dongle to connect to USB-C -- thats what makes this so bizarre! But again, when I use USB-A headphones connected to a USB-C adapter dongle, then it's fine.

 

[BrianBaughn]

The problem can't be with the jack itself because the same issue happens I use an adapter dongle to connect to USB-C -- thats what makes this so bizarre! But again, when I use USB-A headphones connected to a USB-C adapter dongle, then it's fine.

I understand now. That IS bizarre.

 

[DeltaMac]

Headphone I/O and USB I/O use very different paths on the logic board, but ultimately all would be through an I/O chip on the logic board - or whatever the equivalent path would be on more integrated chipsets.

Do you hear any crackling/noise when you simply play music or other audio, through the internal speakers, no headphones attached?
Then, do you continue to hear (or not hear!) the noise during music/audio playing, with the only change is plugging in headphones? Plug into the normal 3.5mm headphone for this test.

You did not say if you tried a headset (with its own attached mic), or always headphones (no attached mic), so the built-in mic on your MBPro is always used.
In that case, maybe the fault is with the built-in mic, which I suppose you would always be using.
Test with a headset w/mic