The June update breaks HiFiBerry Dac support (as did the May one).
But the same fix works.
Download this new overlay and copy it into the overlays folder at the top of your SD card. You will need to remove it from your Pi to do this.
But there’s a wrinkle. The hardware overlay files are now .dtbo rather than .dtb - so you also need to rename the new file and overwrite the one that is already there.
Boot it all up again. You may need to select the overlay in Pi config under My OSMC, and set the audio output in settings.