Screen resolution not viewable

I just purchased my Z80 and during my first round of golf, i see it has many vertical lines in the viewer making it extremely difficult to see the pin. Most reviews say the screen is nice a crisp, mine is anything but that. The screen is full of vertical lines about 2 mm apart. I can barely make out the pin through the viewer. I made sure my firmware is up to date, tried the focus ring and still can't view through the viewer. Anybody know who to reboot this thing to see if that helps?