I have a similar model, and I have been going through the troubleshooting steps the last few days. Forgive me if this seems redundant, but would you answer the following?
- What is the host OS? Is it Linux? If so, have you added your user to the VBOXUSERS group?
What filter do you have for the USB settings? USB 2.0/3.0? What cable are you using, could you try another?
What exact commands do you use to initialize the card? (e.g.: ifconfig wlan0 down, iwconfig wlan0 mode mon, etc.)
Have you experienced any warnings when running airodump-ng?? Try running "airodump-ng check kill"
Hopefully something mentioned above helps out.