Audio dropouts and glitches in High Sierra with USB DAC

[disty69]

Hello everybody at the forum,

 

My system is kind of old, but runs MacOS High Sierra so well, I really I want to fix one problem that drives me crazy!!!

 

So, here it is:

 

My system is composed of the following:

 

Motherboard: Asus P5E VM - HDMI, 4GB RAM

CPU: Xeon x5460 (with the LGA 771 mod)

Graphics: ASUS GT 1030

 

My problem is that when I play music (either with a dedicated audio player or youtube)

and at the same time I do something simple like resizing an App Store window or even click on a file

I get audio dropouts and glitches. If I do nothing audio is playing perfectly.

Everything else works fine.

 

Thank you very much

[PPCnostalgic]

Hello. Is your USB DAC managed by its own driver or the system doesn't need any extension/control panel to route audio signal through?

[disty69]

Hello. The USB DAC is recognised by the OS without any extra driver. I have also tested a completely different USB audio amplifier (again recognised by the OS without extra drivers) and the problem remains.

[disty69]

Hello. I am really happy to post the solution I found after over 100 hours of messing with the OS.

It seems that my motherboard's chipset ICH9 was not supported correctly by High Sierra drivers.

 

After installing the AHCIPortInjector.kext found here: https://www.osx86.net/files/file/4555-ahciportinjectorkext/

the sound problem got fixed completely.

 

I hope other people find this helpful for this or some other related problem.

 

Cheers!