CC Poon recommended I use one when I had my M24. I found I didn't need it though. I was using a North Star transport that could upsample the signal to 24/96 which the M24 could read. Other transports I tried with the M24 had varying results. Personally I would try to get a good transport that matches up well with the M24 and avoid the extra component in the chain and extra set of cables.
