Playback delay issue with IQAudio Pi Codec Zero audio HAT

[jonhelt-hansen]

Hi,
I have a IQAudio Pi Codec Zero HAT (black edition) used with RPI5 and latest Bookworm OS. I am developing an application with time critical audio feedback, but I keep seeing ~2 seconds delay on audio. Using "aplay my.wav" there is a playback delay of ~2 seconds, which disappear if I repeat the "aplay my.wav" command within ~3-5 seconds. If I wait longer the playback delay comes back. This is also what I see in my application.
In the /boot/firmware/config.txt I have tried with
dtoverlay=iqaudio-zero
and
dtoverlay=rpi-codeczero
Both give the same.
I have tested with different HATs and different RPI5 boards - all with same result, so this is general problem.
Any clues on potential solution?

[lurch]

I also ran into this a while ago (back when I was originally testing the beta versions of Raspberry Pi OS Bookworm!). IIRC https://davejansen.com/disable-wireplumber-pipewire-suspend-on-idle-pops-delays-noise/ fixed the problem for me, but I then got pulled onto a different project so I completely forgot to follow up further on it.
(and I was a bit careless and accidentally snapped the microSD card on which I was recording all my test-results, whilst swapping a HAT between Pis 🤦‍♂️ )