When we talk about proof in situations like this, the only honest standard is that two things must align. First, there must be a physically coherent mechanism that can influence the device in a predictable way. Second, the sonic effect must be repeatable in the same environment. When both the physics and the repeatability point toward the same conclusion, the experience is not arbitrary. That is exactly what happens in my system.
The Cambridge MXN10 uses a C7 connector, which leaves the chassis floating without a fixed reference to earth. In a home filled with WiFi, Bluetooth and mobile signals, a floating chassis naturally accumulates high frequency interference because it has nowhere to drain it. This interference couples through parasitic capacitances into the internal ground plane and subtly modulates the reference that the digital clock, the DAC and the analogue output stage rely on. The modulation is small in amplitude but large in sonic consequence, because it affects phase noise, micro timing, dynamic precision and the clarity of low level detail. What the AudioQuest NRG Y2 provides is a cleaner and lower impedance path for this energy to escape, which stabilises the ground plane and lowers the RF pressure the MXN10 normally experiences.
The design of the cable matters because RF behaves very differently from the 50 hertz mains waveform. At high frequencies, energy travels along the path of least impedance, which is determined by geometry, spacing and dielectric behaviour. The NRG Y2 uses controlled conductor layout and a stable dielectric structure that lower RF impedance and guide high frequency noise toward the wall earth instead of letting it scatter or reflect inside the device. Long grain copper reduces microscopic boundary effects inside the conductor, which further limits reflections and standing wave behaviour. A basic molded cable, with random geometry and higher RF impedance, simply cannot provide this type of behaviour.
In my system the effect is not subtle. When the floating chassis finally has a proper drainage route, the entire presentation becomes clearly cleaner and more stable. The grain that used to sit on top of vocals and high frequency details disappears. The sound becomes more dynamic because the micro timing that gives music its sense of drive is no longer blurred by noise induced modulation. The slight hash or haze that used to ride on transients also vanishes, because the ground plane is no longer wobbling under RF load. Nothing is added and nothing is coloured. What happens is that the interference that used to mask fine detail is simply no longer present.
Regarding placebo, I fully acknowledge that expectation can influence perception, but only within limits. Placebo cannot consistently remove grain, increase dynamics and eliminate hash across multiple days, multiple sessions and multiple A and B comparisons under identical conditions. Placebo does not turn on and off with the same precision as an electrical mechanism. The change I hear matches exactly what the cable is doing in the RF heavy environment of my home and the grounding topology of the MXN10.
I am not claiming that every system will behave in the same way. I am saying that in my setup, with a floating streamer in a noisy wireless environment, giving the device a proper RF drainage path produces a very pronounced improvement that is cleaner, more dynamic, grain free and devoid of the hash that the stock cable allowed to remain.