I have had the NZ Tivo since day one and have rarely had problems with the signal to my DSE XH9950 Modem/Router - 'g'.

I have 2 other wireless devices which connect with no/zero problems. A netbook and a PlayonHD Mini.
I can connect the Tivo (eventually) to the network and then it may drop after (say) an hour.
When I go to Network, I usually see Signal:none. At present, I am using a static IP Address (I had to try something).

If I then go to Change network settings, I rarely ever see my network SSID (but I do see some of neighbours) straight away, but it does seem to appear after a minute or so (which is what the instructions on the TV screen say). It may also, bring up another neighbours SSID at this point.
So, if I can see my SSID, I choose it and have to re-enter my network password (I have done this countless times and I can probably remember the keystrokes blindfolded). I add the password and it tries to access the network.

As usual (as it has just done) it invariablly fails.

I am using on the modem:
Authentification Type: WPA-PSK
Encryption: AES
MAC Address Filter: Not Activated.

If I repeat the extercise, my SSID is no longer listed, but others are (two in particular).
As per this time, it was just failed, I have gone back to the point where it shows the SSID's. My SSID is not there and after two minutes it still hasn't show up and after 3 minutes I choose 'Enter network name'. It has remembered my SSIS. I choose WPA and then AES. My password is still there (which seems to be at its whim). I finish and it attempts to access the network. As usual I get a NO6 error.

The DSE modem/router only has one antenna. It is roughtly in the same position as it always has been. The modem is upstairs and the TiVo is downstairs.

Any thoughts?