Call 101 to report a noise problem:
The residents and families of Cathays should not have to tolerate the indignance of having to put up with noise (often from a minority of students, or locals from other districts using Cathays as a throughway).
The students should not have to tolerate loud music or invasive noise (particularly around exam time) and the majority of the students would complain as much as the locals about the noise if they knew where to go.
Calling 101 is the Police non-emergency number. The call will be logged and the Police will attempt to get around to the house or street in question where the noise is reported at.