how to delete AppleHDA.kext - in use (for hmdi audio fix)

[asexymind]

while trying to fix hdmi audio in macpro 2012 running osx 10.13.6, I downloaded the "fix" AppleHDA.kext and an HDMIAudio.kext.
using kextbeast, I attempt to install them in system\library\extensions.
HDMIAudio.kext installs fine. AppleHDA.kext does not install (because kextbeast won't overwrite existing file).

I goto folder /System/Library/Extensions/, select AppleHDA.kex and right-click - no delete/trash option.
ctrl-right-click - nope
command-right-click - nope
option-right-click - nope

I attempt to uninstall in Terminal using
sudo kextunload /System/Library/Extensions/AppleHDA.kext
which does not give me an error, but does not delete the file
&
sudo rm -rf /System/Library/Extensions/AppleHDA.kext
which give me the error "operation not permitted"

I am unclear how to proceed. I assume I need to unistall existing AppleHDA.kext to install new version. I am open to alternate paths.

Thanks y'all !

 

[P1LGRIM]

Does not require Buying Advice - Moved to HDMI Audio.

 

[asexymind]

Does not require Buying Advice - Moved to HDMI Audio.

thx. I thought I already did that. oops.

 

[toleda]

I downloaded the "fix" AppleHDA.kext

No fix required, bad advice; remove.