We could not complain about foam problems either. It depends more on the bath additive. If necessary, you can use the shower hose for help. That way you get wonderfully much foam.
I could also imagine that it depends on the type of bathtub. There have been reports of different inlet noises here as well. Well, that's probably hard to test beforehand, I'll have to take the risk. Otherwise, there's a battery-operated mixer stick and then I'll foam my bath myself.
If it depends on the bathtub type - we have an acrylic tub.