The cheapest form of HF hash attenuation is to add on ferrite on the RCA from the source. AQ makes a variety of them or try Amazon type in "Ferrite noise suppressor" Plenty of sets, ones with a variety of sizes around $12.
You place one (or 2 or even 3) on the RCA wires from your digital source. They cut the HF grunge to a degree. and may be ALL YOU NEED.
Add one to the source AC cord too.
You place one (or 2 or even 3) on the RCA wires from your digital source. They cut the HF grunge to a degree. and may be ALL YOU NEED.
Add one to the source AC cord too.