Thanks for the comment Currawong. I've been comparing Adirvana vs Decibel. Soundwise there aren't many differences I had been able to find. I've noticed that Audivana can change computer's output sampling frequency to the DAC, matching that of the reproduced files, so when playing a 24/88, OSX's Audio MIDI says the output to the DAC is going at 88. Then when reproducing a 24/96, Audio MIDI sampling also changes. This doesn't happen when using Decibel, but I have yet to see what's going on. I need to check the input SF at the DAC. Checked and DAC's input follows what Audio MIDI says.
Looks like it's all a matter of configuration. If you set up Decibel to get "maximum" (not just "high") and tick "adjust sample rate for best quality" then it preserves the file sampling rate. Audirvana + seems easier to configure.
TBH both sound great, A+ playlist and user interface look a bit more attractive. But it's more expensive. Feeling lazy to test Fidelia too, but I should do while Decibel is in demo period.