A1990 Speaker issue

[Mineccia15]

Hello, got a MacBook A1990 from a customer the issue is thee left speaker.

Basically he went to another repair store and they replaced 3 times the speaker and all of them sound distorted/buzzing.
I found a little corrosion around U6400 and replaced it 2 time but I got no differences.

What else should I check?

 

[2informaticos]

Did you test with known good speaker assembly?

 

[Mineccia15]

Yes, I tried from my personal speaker and sounds distorted.
It is not a speaker issue sadly but something on the logic

 

[2informaticos]

Check/replace C6411-14 and C6461-64.
Noise comes from tweeter, or woofer?
You can remove corresponding coil, to check each independently.

 

[Mineccia15]

it comes from the woofer because when I removed the U6400 and tested there was no buzz sound going on.

 

[2informaticos]

Check/replace C6411-14...

 

[Mineccia15]

it is better but not perfect what else can I try?

 

[Mineccia15]

one side of R6481 was not well soldered. Fixed the issue.
Thanks a lot