I have a similar problem and oh boy, what an odyssey. I received my device over two months ago. The mushy, crunchy background sound was there from the very beginning. The funny thing is, it only occurs when I stream any kind of video. Netflix, Youtube, whatever, it doesn’t matter. With Podcasts, Audible and so on it is fine. But that is still a no go.

So now the real fun begins.
I told the support the problem and first they were really helpful, wanted to send a replacement after 4 to 6 emails back and forth. And I told them, I don’t want that. I want a refund, since I was so disappointed in the product and didn’t want to deal with all the stuff attached. I just wanted my money back. BUT they told me the replacement is already on its way, even though I never agreed to that. Weeks pass by, in which I exchange a ridiculous amount of emails with the support, always asking where the replacement is, it didn’t arrive, so that I can send it back AGAIN to get my money AND telling them, they I never wanted the replacement in the first place. Turns out, there never was a replacement on its way, cause it didn’t even arrive after two months. After more Emails, back and forth, finally they start to take some sort of action, I send my (from the start) broken device back to them with the very clear request to get a REFUND, not a replacement (I made this request very very often) . Guess what I got? A replacement. lol. And I was like “okay, I´ll give it an other chance, I’ll try these replacement Ear(2). Maybe this one device was broken, that happens”.

Big surprise: Still the same, weird crunchy mushy unusable sound, even with another pair brand new Ear(2). Such a disappointment. Especially with the support.

I hope the refund process now will be better. So much time went into this whole thing, I should get a refund and a phone or something to compensate the effort I put into that nonsense.