Gulping toilet

[Budd]

Moved into a condo in a 9 story building. Nice comfy toilets that make an awful gulping, or gluging, sound at the end of the flush; quite loud. I notice that the tank is marked 1.6gal, and the flush valve(?) is marked 1.28gal. I have no idea if this difference make a difference, or what the heck is causing the noise, or how to fix it.

Any ideas?

 

[Jamesplumbing06]

Might try just a 2 gallon bucket almost full. Poured straight into toilet. Dumped in. If the noise is less then you need a plumber to adjust tank water level and the correct flapper. If the noise is still there then it’s the toilet design and not much you can do. Water pulling and breaking a vacuum makes some noise. Sone toilets are noisier than others.