[SOLVED] How to disable HDMI audio on Pi 4

[steve4star]

I had a problem where on boot my iQuadio DAC+ card would not always appear as card 0 with the HDMI audio appearing above it.

The solution was to disable audio output for the HDMI ports on my Pi 4 with the following entries in config.txt
and adding a noaudio parameter to the vc4 HDMI overlay...

Code:

# Enable audio (loads snd_bcm2835)
dtparam=audio=off
dtoverlay=iqaudio-dacplus

# Enable DRM VC4 V3D driver
dtoverlay=vc4-kms-v3d,noaudio
max_framebuffers=2

I believe this a pi 4 issue, but may help others out when audio is not available.
More info about the overlay can be found with the command

Code:

dtoverlay -h vc4-kms-v3d

[Tim Curtis]

Is this only happening when specifying dtoverlay=vc4-kms-v3d?

Btw, what your usage scenario where this HDMI driver and not the stock Bullseye driver is needed?

The usage scenario info could be useful because this driver is default on Bookworm.

[steve4star]

Is this only happening when specifying dtoverlay=vc4-kms-v3d?

Btw, what your usage scenario where this HDMI driver and not the stock Bullseye driver is needed?

The usage scenario info could be useful because this driver is default on Bookworm.

I am using a Waveshare 11.9 DSI screen and need to rotate the display.
I think I had to enable this driver to get it working.

I will try and disable the overlay tomorrow and see if what happens.

[steve4star]

As suspected if I comment out the video driver the Waveshare screen does not present. 
However, the HDMI ports do not show in aplay -l so that explains the behaviour I was seeing. 

It may be useful to have an option to turn off the audio for HDMI and an option for the headphones too as the iQuadio driver doesn’t work for me with headphones enabled.