192khz/24bit output with Hifiberry Digi+

Hi, I need Your help.

I Have RPI2 with Hifiberry Digi+, latest OSMC and receiver plugged via optial cable. Everything is playing, but … even I play 192 kHz (24 bit) FLAC file, all I get to the output is 48 kHz. I tried everything I googled, but without any luck.

Can somebody, please, advice me, how to configure device to get RAW PCM (unchanged bitstream) of hi-res audio?

Thank you, Vaclav