wow, thats a strange one. I am less likely to believe it is a problem on your system since you can get on the server in the morning as you stated.

First I would suggest that you make sure your harddrive is REALLY clean. Run all your virus protection and the apps i listed here:
http://www.texasteamplayers.com/index.php?topic=14724.0
to purge your system of nasty crap.

Then run a defrag or two on your system.

when you launch BF make sure that as few programs are running as possible - open up task manager and kill everything that you can


What do trace routes and pings look like to the server during the times you cannot connect vs the times you can?

open a command window and run a ping and a tracert against the IPs:
74.52.161.162:16568 and 74.52.41.162:16569
let us know the results.