I have a triactive tracker on my dog. She's a mutt. She had started chewing herself and scratching frequently. She didn't have flees or dry skin. She was put on allergy meds, then calming treats. Nothing worked. I realized after hours of thinking,why now, that this started after she started wearing her gps tracker. I looked up what the tracker uses to track. EMF and Microwave signals. Both have side effects. She maybe overly sensitive to them. Once the collar was removed, about 12 hours later, chewing and scratching has stoped. I stoped the allergy meds and calming treats. Still no more chewing and scratching. She had made bald spots on her body from this behavior. I share this for any having similar situations. Applying liquid non flavored melatonin to the effected area daily has regrown the hair in her bald spots. She's back to normal.