Available on all ASI6000 series adapters, MRX allows simultaneous playback, recording and mixing of audio streams of differing sample rates and formats. This is accomplished using precision sample rate converters (SRC) that convert all audio streams to a common sample rate (the adapter rate) before mixing occurs.

MRX is especially useful in the "all digital" environment, where the adapter is playing and mixing streams of various rates and must output the mix through AES/EBU at a different rate.

For instance a 32kHz stream could be overlapped with a 48kHz stream and the mix sent out at 44.1kHz using AES/EBU. At the same time, a 44.1khz AES/EBU input could be recorded as a 32kHz stream.

MRX also allows for a 1Hz adjustment of stream playback and record rates, allowing broadcast segments to be scaled to an exact time length.