Sorry for being late but hey, I just registered
After running into the very same issue (same adapter same problem on different Windows 7 machines) I found this post.. and I found newer drivers.
The driver Windows installs automatically when adapter is plugged in and the drivers from Alfa are the same!
Realtek released a newer version just a few days ago which fixes the issue on my end!
Of course you can ignore the Realtek client, but the package found here has the new driver.
http://www.realtek.com.tw/downloads/...true#RTL8188RU