Dietpi ARMv8 64-bit image + Squeezelite I2S audio Hat - NO SOUND

Hello all,

May I ask your lights on a weird audio issue.
I have designed my own Slave I2S audio Hat.
It is working fine on a Rpi 3a+/3b+ with the standard 32 bit Dietpi version even when I compile Squeezelite for 64bit.

I recently saw a 64 bit version of dietpi availlable also for the Pi 3a+/3b+.
I decided to have it a try.
Although Squeezelite is running, I get no sound from my soundcard.
I tried with the prebuild Squeezelite from Dietpi and I also tried to compile squeezelite for the 64bit architecture.

I tried speaker-test -C2 -twav -17 and I get the sound card working.
I finally tried with a basic USB soundcard and with it Squeezelite is working.

So the issue is not my soundcard but I can't find what is wrong with it when running on the ARMv8 64-bit image...

Any help would be appreciated.
Jean