The “Stereo/Mono” grey field you see is normal, because it is not editable.
Quit WaveLab, then erase this folder:
C:\Users[YourName]\AppData\Roaming\Steinberg\WaveLab 7\Presets\Audio Streaming
Does that change something?
If you have still a problem, please show pictures of the Audio Streaming dialog (all 3 tabs).