Is serving very well, but now and then hums

We bought the thermostat in order to incorporate it into our rented apartment in the bathroom. At the function, there is absolutely nothing to complain, everything as desired, the Chill remains pleasantly constant even when the washing machine or toilet flushing start. The exact Chill and is not matter, eventually it's so provides a how to like it, and not by Celsius degree.
Unfortunately, the thermostat buzzes but depending on how the water pressure changed in the large apartment building. One hears the absolute extreme cases, like really seems a little water between hot and cold line to run. You could probably do better, maybe you could replace a part (pressure relief valve). Since the problem but usually only on weekdays in the morning when all the neighbors go to the showers, results, at the price quite acceptable.