RRD Full Graphic slow display update

Hi, I got a problem, my RRD full graphics display seems to have quite a slow update upon navigating the menu, for example pressing the knob will enter the main menu, but turning the knob from info screen to prepare, would have the screen goes blank for about 2-5 seconds before it appears back, this happens only when turning the knob to navigate through the menu lists.

My current electronic is

CH340 Arduino Mega 2560
ramps 1.4
drv8825 step stick
marlin rc3 1.1.0 with ramps 1.4 efb board profile selected

I tried with a spare full graphics controller board, it seems both having same issues, is it the ch340 mega or marlin itself?

Thanks in advance

In case you guys wondering, this is the link to the video
[www.youtube.com]

My full graphic LCD panel scrolls through the menus quickly it sounds to probably be your Arduino perhaps the 5 volt regulator on the Arduino that powers the lcd or something else in the Arduino

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Prusa i3 Rework - Ramps 1.4 - E3d Lite6 - Full Graphic LCD Controller

I will try with my rs323 arduino mega from china as well tomorrow and see how, I also beginning to suspect the ch340 arduino type ain't cut for it

i tried with my spare mega that's using the atmel ftdi chip, it is also the same issues

Turns out to be two of the pins were connected after I tried other combination with/without sdsupport enabled in the config.h then it was okay after I swapped into another adapter and didn't noticed the defects. I already disconnected those two and tried it, it worked like a charm

Here's the picture [share.pho.to]