DAC resampling in 24 bit

Hi,
I use Volumio 2, with the last version.
I have a DAC suptronics.com/miniPCkits/x4000.html
I have a problem if I don’t resample my music (FLAC, for example) from 16 bit to 24 bit.
So, the remaining issue is with the start tone of Volumio : it is not ressampled and it becomes an bad noise.
Has anybody an idea ?

Thank you