If both a USB cable and LAN cable are connected at the same time, the USB connection has priority.

When scanning with the scanner connected to a network, because the image transfer speed is prioritized, the image quality is lower than when scanning with the scanner connected via a USB cable.

In the scanner driver, you can set the image quality to the same level as the level that is set when scanning with the scanner connected via a USB cable. For details, refer to the help for the scanner driver.