USB DAC not working Krypton beta 1

Using the same Libreelec release (Alpha 5) with Kodi Krypton beta 1 on
a Solid-Run Cubox-i (imx6 based) and on a WETEK Hub (S905 based)
my UAC222 USB DAC does not work with the latter. An USB DAC
is recognized on the Hub and can be selected. But sound output
is still only on the HDMI. On the Cubox-i everything works fine
an sound is going thru the DAC.

Please help.