It's true, I remember reading a thread where someone wanted to return a piece of gear.If the changes are immeasurable, then they certainly are inaudible. If they are inaudible, they don't matter at all.
I can see a mechanical device like a transducer "breaking in". But if that shift is large, it's probably going to continue to break in and eventually break down. That's called "wearing out" not "breaking in".
If you want to know what "burn in" REALLY is, I'll let you in on the secret... Burn in is the excuse retailers use to try to get you to keep something you really don't like until the return for refund window closes. Next time a salesman tells you that something takes a few weeks to break in, ask him to put in writing that if it doesn't break in properly in X weeks, you can still return it for a full refund. Watch him backtrack and start telling you that burn in is very small and maybe inaudible.
The representative of customer service for the company posted that the person should burn-in the device for at least 4 weeks. It's a smokescreen to try to get people to get past the return window.
Not only that I won't mention the name of company here, as they most likely a sponser. But they even include a burn-in cable with the product for their convenience, not ours LOL.