Ok so I have had my xterra less then a year. I use it a couple times a weekz and I am pretty rough on my machine. I do keep it clean. So last week when I turned it on switched to all metal mode The thing starts blinking in pinpointer mode display is jumping back and forth with Ps then a minute later Pa but wont come out till i turn it off. Turn it on in a discrimination pattern it does the same thing. Any help or suggestions mikee