The wireless transmit rate of my MacBook Core 2 Duo is extremely unstable. That is, when I connect to my AirPort Express the transfer rate is good for about one minute and after that it suddenly drops (option click on the AirPort icon shows a transmit rate of 1...).
The strange thing is that when I then click on the AirPort icon next to the clock and new networks are being searched, the rate gets normal again for about 10 seconds. Then again all running downloads and page load stop until I click again.
I use the same network with a MacBook Pro without any problems. I've googled this issue, tried to switch wireless channels, switched back to 802.11g mode (it runs on n and g compatible mode normally) but nothing helped so far.
Any ideas what could cause these transfer rate drops?
Not sure if that's of any use but in the AirPort Utility it says Signal -24, Noise -95 and Rate 1 (it raises when I click the AirPort icon).
One solution seems to be to switch to 802.11n only 5 GHz (2.4 GHz does not help). The downside: iPhone and many older notebooks don't support it...