ADAU146x SRC Latency


I've got an ADAU1462 project that takes i2s in, sends through ASRC to internal sample rate of 96kHz. 

When measuring the end-to-end latency of the system with fs_in = 48kHz, I get 1.521ms, and when I change sample rate of input to 96kHz, the latency drops to 583us. When I increase sample rate again to 192kHz, the latency drops to 333us.  The internal ADAU1462 processing is still all happening at 96kHz, so I have to assume that the ASRC latency is dropping by a rather significant amount depend on input sample frequency.

Does this make sense? I can't find any sort of ASRC latency specifications in the datasheet.