It might be because of the clock of the CPU or the dac being 24Mhz. 24MHz/512=46.875KHz Edit: or 12, 6, 3... 24MHz/512=46.875KHz 12MHz/256=46.875KHz 6M

It might be because of the clock of the CPU or the dac being 24Mhz. 24MHz/512=46.875KHz Edit: or 12, 6, 3... 24MHz/512=46.875KHz 12MHz/256=46.875KHz 6MHz/128=46.875KHz 3MHz/64=46.875KHz...