WiFi drop-off problem still dogging MacBook lines?

Owners of the latest MacBook models are still complaining about erratic WiFi performance and drop-offs. While the postings in the discussion boards keep piling up without resolution, some point to new solutions. I wrote about this issue more than a year ago.  At the time, some of the suggested fixes were to check interference by other routers in the area, and to forget about 802.11N compatibility. This latter issue appears to no longer be an issue. But some owners say this problem is still be present, even on new MacBook Pro models and the MacBook Air. Several readers found that their PCs held a wireless connection better than their Macs. Horrors! For example, here's a letter from Canadian reader Mtbguy:

Any updates about the Mac WiFi problem? I have a PC beside my MacBook Air and it's painful to see my Mac dropped connections and slow downloads while my PC flies like a bird on the waves of WiFi. I have tried everything and still the PC way outperforms the Mac. Mac is supposed to be the jewel of the multimedia age, but it isn't since I can't connect to it on Wifi, and in Mac wisdom they did not put an Ethernet connection on my new MacAir.

There are hints at fixes.

First, there's the antenna. I read of a number of posts in boards about loose and faulty antennas. One guy bought a older MBP enclosure on eBay and then had a technician swap out his current antenna with the one in the used case. He said it worked "flawlessly" thereafter. The Apple part number for the MBP is 922-7276. I see that the part costs $29.95 at iFixit when it's in stock. No surprise, it's unavailable. If your machine is covered under Apple Care, then get on Apple to fix the problem. However, there's another potential culprit that you might want to check before scheduling a visit to the Genius Bar: third-party cases and skins. In a recent trip to my local Apple Store to get the DVD drive in my MBP repaired, I talked about this issue with the Genius helping me. He said that the inks used in even very thin skins for the notebooks can interfere with WiFi reception. Even hard plastic or fabric cases can make a difference. Blogger Bibliosk8er found that his clear, plastic case was the problem.

I was sitting right next to our WiFi router getting super slow connectivity. So I decided to remove the transparent plastic case I’d bought for the machine. It sure did look cool. As soon as I removed the case (which is made specifically for MacBooks and costs about $30), my WiFi connection improved by about 1000%. In fact, it became normal. No more problem. So if you have a plastic case on your MacBook, and your WiFi sucks, take the case off.  Amazingly, 2 millimeters of plastic is enough to ruin your signal.

So, take the MacBook out of the case or skin and check if that's an issue. In addition, check your WiFi performance in different locals. Your problem could be your building and neighborhood more than your MacBook itself. My apartment is in a sea of routers. I've used KisMac, a free open-source stumbler and WiFi scanner application to look at my neighborhood. It's a bit scary (the application) but the program will reveal a lot about your WiFi environment. http://trac.kismac-ng.org/ If your router is on the same channel as another in your area, make a change and see if that helps. Tip: if you're connected with WiFi to a router, hold down the Option key and select the AirPort icon in the MenuBar. It will show the router's MAC address, received signal strength indication (RSSI) data, channel info and transmit rate. When you mouse over the other named WiFi routers in the list, they show the the RSSI number and the security mode. Read: The MacBook's mysterious WiFi dropout problem is still unsolved