Has anyone here preformed any comparisons with the RX-888MK II being powered from computer USB vs powering via a USB hub with a quieter/cleaner power source? Or does the RX-888MK II have sufficient filtering on the input?
I think the RX888 has sufficient filtering to prevent differential mode noise entering the receiver by means of the DC power input.
However, any external device, can still introduce noise by direct radiation to the receive antenna, or via conduction onto interconnecting cables, which may, by means of circulating currents, still enter the signal path along with any wanted signals.
It is therefore worthwhile adding an effective RF choke on the USB-3 cable, as a further precaution against noise ingress.
Just a few clip-on ferite cores are not that effective at frequencies below approx 50MHz.
http://www.karinya.net/g3txq/chokes/
Regards,
Martin