Sounds like it’s water hammer.
It will either be easy or incredibly hard to fix.
Probably the first step is getting a plumber to examine the pipes and determining if there are any defects in the pipes that need repairing. Then installing a water hammer arrestor.
If that works, all good. If not, then the hunt begins for the cause and solution begins. That can be expensive and take a long time.
As to who is responsible, I’m sure someone more familiar with strata law will provide the answer.