MacBook Pro 15" can't find wireless preferred network after wake-up

Question

Hello all
I've this problem with a MBP 15" (SnowLeopard 10.6.6): it doesn't find my preferred wi-fi network after waking-up from sleep.
Settings:
- on the MBP there's a preferred Location for this wi-fi connection
- wi-fi, DHCP and DNS managed by an AVM FritzBox 7050 (not visible SSID, MAC restriction, WPA2 pw)
- the channel I've set is different from other wi-fi around the building
The same network works perfectly using an old iBook G4 and an iMac, and other Windows PCs too.
Sometimes the MBP AirPort card just can't find the preferred Fritz network, while it does sees other wi-fi in the same building. Even using NetStumbler doesn't help.
I need to try to add manually "another" network several times before the MBP joins the Fritz wi-fi.
I already deleted and recreated the preferred network.
Is this a known software issue, or it can be a faulty AirPort card ?
thanx
Gabriel

Answer 1

Hello all,
after a lot of testing, using both the MacBook Pro and an old iBook G4 (the latter was working perfectly), and having on both machines some wi-fi sw such as KisMAC and iStumbler (while watching the wi-fi monitor on the access point consolle), I found that:
- the MacBook Pro is much more sensible to noise;
- it is better to use a channel with little noise, even if the are other devices on overlapping channels.
Eg: I found the channel #13 was free and there was only 1 other PC on #12, but there was a lot of noise. After trying all the channels, I  decided to use #4 because there was little noise, even if there were many PCs around on #5/6.
So, don't care (as one should usually do) too much about not overlapping channels; instead, search for channels with little interferences.
I hope my solution can help you
G.