Hello! I have the exact same problem, although I do have some crusting and itching once in a while in the same place behind my right ear. What I do is when I shower in the morning, I take a pair of rough bath gloves, soap them up, and gently scrape away the dead skin.
When they are absorbed, they can be released in sweat through skin. Foods like yogurt, onions, garlic, red meat, cabbage, spices like coriander, and asparagus may result in increased body odor when consumed in large amounts. When you have a diet rich in proteins, you may have vinegar like smell on sweat.
But the weird thing is that certain smells are wrong during my aura, kind of like a odor hallucination. The one that I have been able to identify is that sweat/body odor will smell like beer. I do not know if other things smell wrong-considering it took me 8 years to figure the sweat/beer thing out.