iFi hip-DAC setup?

hi there, i just bought a new secondary portable dac, the hip-DAC from iFi, and i plan to use it with the trusty Audirvana,
i have some question regarding how to setup the Audirvana if i want to use it with the hip-DAC with bit perfect mode, please kindly check my screenshot is there anything i missed since every files i play seems to be always upscaling to 32bit.

also should i choose large ASIO buffer on or off?

thanks in advance.

Settings are ok. Damien said buffer on is good too, but when not upsampling computer is not working much.

Not sur for your volume control, i think it must be set to 100% for dsd playing.

If you look up your debug info, expect to find only 32-bit formats, your IFI will accept. Mine older Nano DSD does so.