The display is either defective or otherwise unusable when used with other i2c components attached. It can be used alone just fine but its addressing is problematic.

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Product details
The SparkFun Qwiic OLED Display offers a sharp, professional user interface in a compact 1.5-inch form factor. Featuring a 128x128-pixel resolution, this monochrome white-on-black display uses Chip-on-Glass (COG) OLED technology, providing a 1:1 aspect ratio and a high-pixel-density canvas ideal for custom graphics and data plotting. Because OLED pixels emit their own light, no bulky backlight is required, resulting in superior image quality and "deeper blacks" compared to traditional LCDs. Versatile Connectivity Whether you need rapid prototyping or high-speed data transfer, this board is designed to fit your workflow: Qwiic Connect System: For the most straightforward integration, the board features two Qwiic connectors capable of I2C communication. Simply plug it in using a Qwiic cable to start displaying graphics and text immediately with no soldering or breadboarding required. SPI Capable: If your application requires faster refresh rates, we have broken out standard 0.1" pins for SPI communication*. By eliminating the need for a backlight, chip-on-glass enables this display to remain thinner and more power-efficient than standard LCDs. *Using SPI requires cutting traces on the back of the board and ensuring your microcontroller uses 3.3V logic.
All reviews
Works better than advertised. I also had no problem running this at a Wire clock of 1000000 (fast mode plus) on an 8 inch long QWIIC cable. One minor note is that the display is not set flat against the breakout board (see photos), which could be an issue for some. The library examples ran straight away without issue. Try Wire.setClock(1000000) to improve your display time, it worked for me.
