USB DAC sampling rate is limited to 48kHz

[Greenstar]

Hi, I'm using Poweramp for about 3 years now. Recently, I bought a USB DAC called "Meizu Hifi Audio Pro" .

When I connect it to the phone and play some music via hi-res output, PA says it's using 48kHz sampling rate instead of 192kHz that I selected. 

I'm wondering whether this problem is related to UI issue or actually it's limited to 48kHz.

btw, my phone is OnePlus 3

Thanks.