Dc 50 problem

I wonder why it's only with the 50s. We probably had 15 collars some were on dogs at the truck and I had two dogs with 50s on only one of them did it the other was on my sometimes good dog haha. The place I was hunting on isn't nothing but pine trees and briars it's a powerline maybe 1 mile away but that shouldn't have messed it up I hunt around them some and it don't seem to interfere. Tommorow when I get home I'm going to turn on that collar for a while and see what it does. I would think if it does that regular garmin should fix that at no cost shouldn't they? So far I have not been impressed with the dc50 collars one bit. I have started putting a quick track collar on some of my dogs to for reasons like this but i did not have one on this dog.