Omxplayer output to Audio DAC SHIM

Hi all

I’ve just got a new Audio DAC SHIM and hooked it up to my Pi 3 A+
When I play back a .wav file in VLC player it’s all great and the audio file plays via the 3.5mm jack output on the DAC and sounds great.
The problem I have is I really need to be able to launch audio files from omxplayer and I can’t get the output to route to the DAC.
I’ve tried -o alsa which does send audio out of it but it’s just a really short burst of digital noise.
I’ve checked and the file I’m playing back is 44.1khz @ 16bit so it’s not a sampe rate problem as far as I can tell.
Does anyone have any ideas?

Many thanks in advance
Dicky

The Pi Foundation switched to Pulse Audio not all that long ago. Might that be your issue?