Have any of you had any problems with Hand dermatitis? I keep getting these little micro-blisters on my left hand, I play mostly with a bow so I am guessing that is why my right hand does not have them. Rumor has it that "nickel" can be a major cause of this problem. I am using Helicore Hybrids which I am guessing may be nickel. Never had the problem until the new strings.