Safety aside, those people should be fined for an excessive ugly bath.
Regarding the clicking every 30 seconds, I say go with whatever the little voices in your head tell you.
Since you said high end, I wonder if the noise is coming from some type metering valve built into the faucet set for backflow prevention? It's not a very good guess, but it's the best my voices could come up with on short notice. If they change their minds, I'll get back to you.