What is the stated latency of the PSM300 system? That is, from analog in to analog out, what is the expected latency? As there is DSP in the signal path in both the transmitter and the receiver, there must be some (minimal) latency for this system. "24-bit digital audio" term raises the latency question because any signal path that includes DSP necessarily introduces some measurable latency.
End-to-end latency, using a 1kHz input signal, is less than 0.7millisecond / 0.0007 second.