Display screen I2C - U8g library - strange graphic!

Hi all

I have an I2C display from hantec, and have sussed out that I can use this with U8GLIB SSD1306 declaration:

U8GLIB_SSD1306_128X64 u8g(U8G_I2C_OPT_NO_ACK);

I have two displays of slightly different sizes that work in the same way, however the larger ones have a strange line down the side.

I'm 99% sure this is software-related because depending on where I write text to the screen it changes a bit, and sometimes when I change the code it almost completely goes away.

I tested resetting a number of times and the strange right hand graphic only ever changes when I change the code...

I don't mean "software fault", more "maybe I got the wrong settings".

Here's what I am seeing:

Any ideas?

how big is the screen in pixels?

have you tried a sketch that puts on/off all pixels every second?
for x=0 to maxX
for y =0 to MaxY

just to see if the pixels that form the line is addressabble

Maybe, this is a SH1106 controller (instead of the SSD1306):

U8GLIB_SH1106_128X64 u8g(U8G_I2C_OPT_NO_ACK);



Thanks Oliver!