Problem with lines on lcd 320x240 from mcufriends.com

I have a lcd from mcufriend.com and got it running, it shows all grafics and characters , but allways with lines or stripes in forground.
The board is pluged to the uno.
After init and reset these lines apear.
I am using arduino uno, tftlcd and utft library, the grafictest file works, it works with 8bit data,
I changed to arduino nano, but nothing helped.

Is there anybody who has that problem solved, so tell me how
Thanks

Hi and welcome.

the grafictest file works

Do you mean that that one works with or without the lines you see ?
If a test sketch works good and some sketch you made doesn't, show that sketch (and put it in [code] [/code] tags).

the grafictest file sketch works and some others ,too. But I allways have these stripes wich do not disappear.

Hmmm.

I've got a vague remembrance of a topic where something like this was discussed.
I think the solution was to power it from 3 volts instead of 5 volts, and that has something to do with the internal inverter/power supply.
Perhaps a few capacitors can help, but to know for sure some schematics would be helpful.
These displays aren't very well documented, so that is a problem.