I'm a longtime Mac user (20+ years) and have owned more Macs than I care to count. I also can't seem to get logged into the support discussions under my usual username, but I digress. I upgraded to a new MacBook Air about two and a half weeks ago, opting for the 13" i5 model. I took it home and was impressed by its blazing fast speeds. A few days into use, however, I began experiencing intermittent and unexplained chokeholds on Internet access via my wireless network. I've done hours of troubleshooting with a colleague on this, eventually tearing down the home network - AT&T DSL - and rebuilding it. I also ended up swapping out the first Air for the one I am currently on, the 13" i7 1.8 GHz model.
Here's the symptom: I'll be browsing or viewing something on the web, checking mail via Mail.app, etc., and the network connection suddenly drops precipitously - pages take several minutes to load, or stop loading altogether. Mail.app is unable to check or retreive mail. When I test the connection throughput using speakeasy.net's speedtest, my typical 5.17 Mbps download speed drops to 1.x or slower and takes minutes, rather than seconds to complete. During this time, I have _full bars_ on my Air. This happens in different physical locations in my home. This does not happen to any of the other 4-5 machines and myriad devices used to test alongside the troublesome Air (among them, a 2007 series MacBook Pro run 10.6.x, a late 2009 MacBook Pro running 10.7, a 2008ish MacBook running 10.6.x, an XBox, two iPads, two iPhones, an Airport Extreme, printers and probably other stuff I'm forgetting).
Here are some things I've done, in chronological order:
- After many hours messing with the 2Wire-as-wireless-router, I reconfigured the network to use AT&T's 2Wire router as simply a modem and connected my Netgear wireless router (auto-negotiating mode, set to channel 5 at present but also set to auto-select channels in the recent past) to serve out WiFi. All other machines are able to use this setup successfully (but also had no trouble when it was just the 2Wire modem/router combo). This has made no real appreciable difference on the problem with the Air, as far I can tell.
- Swapping out the first MacBook Air for the current one, the i7.
- Run Keychain First Aid and followed other suggestions as described here: this resulted in an error in my Keychain that was corrected by running Keychain First Aid as follows:
Permissions incorrect on ~/Library/Preferences/com.apple.security.plist, should be -rw-r--r-- , they are -rw-rw-r--
This was repaired. I also told Keychain to "allow all applications access to this item" in the Access Control settings. This did not result in a solution, as the slowdowns/chokes continued not long after I changed this setting.
I have spent probably 10 hours total troubleshooting this problem, and am probably glossing over some of the things I've checked and tried, but now I'm looking for more suggestions, as well as any other confirmation that others are having a similar problem. Again, this is not a case of losing bars on the Wifi indicator, and all other machines are working without incident on this network. It's the Air that is choking.