Regarding the high pitched tone in the house, it sounds like a smoke detector going bad or with a failing battery. if that is not it, turn off one circuit at the house breaker panel at a time until the sound stops... the appliance lighting balast or etc causing the noise will stop when you unplug each device on that circuit... and in the case of lights, turn that light switch
off. Then replace or repair that appliance.
The high pitched noise is quite unlikely to be coming from the house wiring
itself...but it could be. 0.5% chance perhaps, in that case the electric utility company can arrive to test it but as a last resort... it is most likely a lighting ballast or appliance creating noise... including smoke detectors.
If that fails to work well enough for the speaker issues plug your speakers and computer into the this device, chances are nearly 100% that it will eliminate the *speaker difficulties.... but not the house noise.
I am off to the dentist shortly I will respond when I return.
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