Hi, I just bought a new router dual-band Asus rt-n56u. I set it up with 2 SSIDs 2.4GHz and 5GHz. All bands are configured with WPA2 encryption I installed the latest mountain lion on my MBP late 2011, and I didn't have any issue with the old router. However, the wifi issue has started to happen since I bought the asus router. The problem is that when I start up my macbook, I cannot see 2.4GHz access point on the list of AP, but I can see the 5GHz. However, whenever it gets connected to the 5GHz AP, then I can see the 2.4GHz AP appearing on the list. I don't have any problem with my windows laptop, iphone and ipad. Another problem is that, I don't use the 5GHz connection with ML because it's very sluggish. I know that there're a lot of Wifi issues with ML. I tried different solutions suggested but I can't solve the problem. One thing I haven't tried is to clean install the ML. Any suggestion will be appreciated! Thanks!