using a phat dac on pi 3

Does anyone know how to configure LibreELEC to work with a PHAT DAC sitting on a Pi 3?

Quote from awiouy

In terminal:
dtoverlay hifiberry-dac

If it works, add that command to config.txt: Config.txt - LibreELEC

Thanks so much for your reply awiouy.

I used putty to edit config.txt per Config.txt - LibreELEC

Have tried both:
dtoverlay hifiberry-dac .....and
dtoverlay=hifiberry-dac

but neither works I fear.

I think my soldering job on the Pimoroni phat dac is ok. Pity this doesn't work so far as at £12 the phat dac looks such a bargain?