questions after implementation

[ntzb]

Hi!
I just got my 2.42" OLED and the D1 mini, so immediately went for the implementation.
this is some one sick plug and play! even though my OLED is SSD1309, it worked in a matter of minutes.
very VERY nice work, this repo is a full solution (firmware + awesome webui), and should definitely be getting more traffic.

now some questions -
I noticed two issues, that exist even after compiling my own firmware with controller changed from SSD1306 to SSD1309:

1. the OLED is making some annoying static noise, which gets louder as more text is presented
2. the contrast setting does not work

do you have any idea why?