WH-1000XM5 Confusion

I’m new to Sony Headphones, OTE headphones, and noise cancelling headphones, so forgive my ignorance. My 4 day old XM5s consistently make popping/crackling, high pitched ringing, and static noises during the noise cancelling and ambient noise modes. Did I miss something in setup? Are my headphones malfunctioning? I am completely puzzled. I splurged on these and I’m so disappointed.