There is no dedicated forum for DHP-309AV, so I am posting this here...
I recently bought a DHP-309AV PowerLine AV 500 Network Starter Kit and noticed that traffic between the two adapters causes intense audio noise to be emitted through the speakers of my Logitech external audio system connected to my main computer. The system is powered from an electrical outlet different from the one used by a DHP-309AV adapter although they are on the same electrical circuit. When someone is watching Netflix or streaming something on the downstairs computer connected through the DHP-309AV link, I hear rhythmic bursts of high-frequency noise from my speakers that completely ruins whatever I am listening to -- whether music or speech. And even when the line is idle I still hear frequent pops apparently caused by data packets exchanged by the two adapters.
This is clearly not DHP-309AV's fault but the result of poor noise filtering on the part of the speakers' power adapter. So my question is, what power filters can I possibly use to block the noise from leaking into the audio system's amplifier?