Since both are TWAIN devices and the software isn't smart enough to know which TWAIN device you're wanting to use. You'll have to tell the software what device to use and you'll have to tell it every time you open it.
In the software you use to get the images from the scanner, for example, look for a "Select Source" option. Often it's under File but it could be anywhere, depending on the software. Once you find and click on "Select Source" (or whatever wording that software uses), you should get a small window with both devices listed. Choose the scanner.
The same process applies when wanting to access the camera. Tell the software first which device to use.
At least, that's the process I have to go through.
Linear Mode
