I used this for almost three years, thinking it was OK and unnoticeable in my signal chain. Here and then there was a signal dropout that was corrected by reconnecting cables to the unit, but I didn't think much of it.
That was until I rearrenged some of the hardware here and got a 500 series housing with a linear (instead of a switching) power supply. Then suddenly both stereo compressors routed into the NYS-SPP started behaving super oddly (one went mono unless on bypass, the other lost 6db on one channel -if- on bypass).
A quick test connecting directly into the interface revealed both comps were perfect. Repatching to other channels in the NYS-SPP resulted in the same outcome. The last test, running mixes through it, caused both my compressors to sound weirdly gritty and aggressive in the high-mids, but while connected directly to the interface both of them sounded cleaner too.
This is a poorly built unit, my replacement (costing three times as much) is on its way. It does add distortion depending on the level and complexity of what is being routed, and therefore I cannot imagine that it wouldn't affect quieter signals too even though this is way less noticeable. Better not skimp here (by having a unit like this handling all your signals).
