When I had a W4S MS1 Music Server I used their USB decrapifier and it helped but not as much as the ISORegen. I also found using 2 ISORegens back go back being even better. Sold the MS and bought an Innuos Statement and sold the W4S and ISORegens and the LPS's that powered them.
My DAC is a Terminator Plus that prefers I2S so I tried a $600 Denafrips Iris DDC and clocked it with the Terminator Plus. To my surprise the Iris completely transformed the USB. Even without clocking it clearly improved the USB from the Statement.
If your DAC takes I2S and you have a Phoenix try a DDC.