I was just browsing through my Mac's applications (utilities section) when I came across a program called 'Audio MIDI Setup'. In its setting it states 'format', represented by a frequency and a bit size. These setting can be changed to different numbers, frequency from 44.1Khz to 96Khz and bit size from 16bit to 24bit.
Is this the upsampling that my Mac can perform or something else? Also what would it be best to set these setting to?