From one of the links elsewhere, they're claiming it doesn't: "[...] the relative speed of the cooling fan (which does not introduce vibrations) [...]". Perhap

From one of the links elsewhere, they're claiming it doesn't: "[...] the relative speed of the cooling fan (which does not introduce vibrations) [...]". Perhaps they use the fan to initially cool the sensor and then switch it off and let the Peltier cooling maintain the temperature or something?