Crackling sound from bath

I had my bath installed incorrectly, on foam instead of mortar even though the instructions specifically said not to install on foam. I was made aware of the issue by a loud popping noise in the walls from the drywall being pulled by the bath when it emptied.
I had it pulled out and reinstalled on mortar. Now I am hearing crackling noises underfoot. I am unsure of whether this means the bath needs more support or that the bath itself is damaged.

Here is a link to the video of the noise https://drive.google.com/file/d/1qXFKjG ... p=drivesdk