Allergic to nylon collars?

[ChickensHaveNoEyebrows]

Ok. Hear me out. Jasper (he of stench fame), started to smell bad again. The musty stench seems strongest around his neck/shoulder region. I've used the malaseb again. But...I've had an idea. He is forever kicking/scratching around his neck at his collar. He will walk maybe a 100yds, sit and scratch etc. So it got me thinking. He is on his second collar as he outgrew his puppy one, but this one is also nylon. Is it in any way possible that the cause of all the hassle has been the collar? Can dogs be allergic to nylon collars? After research via google, it seems that a musty stench can be caused by an allergic reaction causing the sweat glands to go in to overdrive and allowing a yeast to develop on the skin. Any thoughts?

Sounds more typical of a dietary intolerance tbh, has that possibility been investigated?

I changed his food to Burns (was on Royal Canin) and that seemed to help some. However, I did buy him some new treats this week

Many years ago I had a rotty that kept getting sores which then scabbed in his neck area and the vet eventually said that he thought he had an allergy to his chain collar,we only used a halti on him after that and his neck cleared up,so it is possible that your dog is allergic to his collar.