I bought a Marshall Code 50 amp and the LCD display lights up but will not display any text at all.   I want to fix this problem so I can use my amp again!  I tried to use bluetooth with the Gateway app but It won't let me edit my settings on the app it doesn't do anything.  If anyone knows how I can get the display fixed or to read text please voice your answers.   Also the factory reset does not help.  Thank you