I had a great experience first time waxing a chain. I bought a new bike with 12 speed di2 105, and cleaned the new chain of its factory coating with several baths of mineral spirits (mineral turps as they say down under), then with 1-2 baths of denatured alcohol. Each bath has just enough to cover the chain in the Tupperware I'm agitating in. Then a crockpot with Silca Secret Chain Blend. I can't remember what temp the wax was at, but it was hot. The chain went in and soaked for long enough for the wax and chain to both get to the right temp, then I swished the chain in the wax for a bit.
The chain was quiet from the start, and I'm 300+ miles in and it's still quiet. In the smallest cog, I can feel the vibrations of the chain going around the pulleys and tiny 11 tooth cog, but that's not noise due to an inadequately lubed chain. It's my first rodeo with di2, so I'm probably not dialed on the rear mech yet.
Do you hear metallic squeaks of metal on metal? If the chain and wax were not hot enough, maybe it didn't work into the small spaces. But just hearing the chain make contact with pulleys and cogs isn't worrisome. At first there is wax working out of the spaces between the plates and the chain needs to loosen up a bit.