It pointed out that “all” other current GaN based amps use existing modules with chips that are currently used in non Audio devises like power chargers.
@mglik If he's getting semiconductor devices made for him I can see that happening. Usually you have to buy quite a lot of such devices to get any semiconductor manufacturer to pay attention to your order! But he might have an in with one of his former employers. But FWIW the chips used in switch mode power supplies have a lot in common with the requirements you face in building a class D amplifier.