Help needed to eliminate unwanted noise from tweeter

@ellajeanelle Thanks for your hint.

I am not sure if this is due to WIFi/Ethernet as my WIFI is always turn on. When I unplug all except E280 and CDP-997, there’s no noise. Even non-ethenet/WIFI equipment like Denafrip Ares II does produce the noise in standby mode.(without playing any music, I am not sure if interconnect XLR or RCA is the culprit?)

FYI, I am using hybrid/Mesh network, Access Point at my listening room then short ethernet cable to my streamer.

Does the noise come from both tweeters?  If so it sounds like you have a noise issue somewhere.  Do you have a power conditioner?  Or I guess it’s possible you have blown tweeters.  That’s all I got. 

@soix Thanks for your response. Yes, both tweeters when these two (2) units DAC and music streamer are connected. There is no noise when I connected my CD player... can’t be the tweeter issue?! Yes, as my first post stated I am using Novaris Surge Protector/Noise Filter.  
 

Will the iFi Ground Defender help?

The only other things I can think of is to try to connect the noisy components to the input of the E280 and CDP-997 where you know there’s no noise. Also, if there’s enough slack on your cables and wires try holding the noisy component in your hands and moving it around in the air. Maybe it’s too close to a transformer of another component. Maybe the component itself is the culprit? Try distancing/ separating power cables and audio cables (don’t bunch them together. Has this noise always been there? Did you change something recently? Is the noise less at night than during the day? Have you tried a different outlet? If the problem comes from your house wiring you might need an AC voltage regenerator, but they can get very expensive (thousands). This is the only sure way to get rid of any AC noise. A surge protector or filter WILL NOT eliminate noise from your house wiring.

Removing/swapping components, one at a time, you should be able to narrow it down to one faulty component. 

However, the hardest problems are when 2 unrelated factors combine to cause the issue so it could be harder to figure that out.

Removing/swapping is the path forward.

Jerry