Why is providing a quiet environment, potentially minimizing high-frequency electronic noise, important for fancy mice?

Because they use ultrasonic vocalizations (USVs) for constant communication, and environmental noise outside human hearing might be disruptive to them.

Fancy mice live in a world dominated by sound frequencies far beyond human registration, communicating extensively through ultrasonic vocalizations (USVs). These high-pitched sounds are used for critical functions such as expressing distress, coordinating social needs, and courtship displays. Because their auditory world is so rich in frequencies humans cannot perceive, environmental factors that we perceive as quiet might actually be acoustically disruptive to the mice. If a mouse exhibits stress signals like pacing or excessive hiding, the source could be an inaudible, high-frequency electronic noise. Therefore, maintaining a low-vibration, quiet environment is necessary not just for general comfort but specifically to avoid interfering with their vital, constant, non-verbal communication system.