What DAC are you using?
If it uses an ESS/AKM/TI (examples) DAC chip, there’s a good chance it resamples incoming PCM to a higher sample rate... I assume they do this because it is useful... and it’s not to add more information...
There are some that believe doing some DSP before the DAC can be useful...
Sabre dacs do not convert to pcm.
Here is a statement on this matter.
Statement on ess sabre dacs.
Most of inner details are not in the data sheet....Sabre DAC works in purely DSD mode, the signal path in this mode is 1 bit input >32 bit fader> DSD filter performed in DSD domain > 6 bit DSD (DS PWM) DAC > analog
The fact that the DAC is 6 bit DOES NOT mean it's not DSD. Basic DSD is 1 bit but it can be any number of bits, in the case 6 if it helps the performance.
Number 1 is a subset of 6 - a 6 bit DSD offers better D/A performance than 1 bit , that's why it's there. It's still DSD though. Sabre in DSD mode DOES NOT use interpolation filters or any other PCM processing ...In fact Sabre DAC sounds better in DSD mode because signal path is simpler.
Examples of non-direct Native processing is when a DAC uses a SABRE 90XX chipset. The DSD signal is digitally processed, usually to 6 or 8 bits but remains DSD and is treated with DSD filters (to remove noise shaping artifacts) and then sent to the analog side. One could argue that FPGA processing like PS Audio’s Directstream, where one bit DSD is converted to 30 bit, 30Mhz, then processed “down” to DSD128, is another example of non-direct Native DSD processing.