Yeah there seems to be issues. I have two of them.
Bought the second one because the first one's display was faulty. The first one I bought used and the display screen would show 90 percent of the screen, but was missing display characters on the LCD.
Second one seems to be OK. I would say to anyone to be cautious buying used because I'm eventuality going to sell the first one with a BOLD disclaimer. Sucks that I will have to provide a disclaimer as an owner and never saw a disclaimer from the manufacturer..