Half-Life Source engine and network problems

Here is the problem:
In any of the half-life:source engine games my connection drops for 10+ seconds.  On one map (2fort for hl2:dm) I would drop connection right infront of the enemy spawn after the first ramp room, everytime.

I am getting good ping otherwise.

Wireless, D-Link g router, Cisco PCI card (b)

any ideas? I guess I could try a direct connection to my router to see if that solves it.

Are you disconnected or do you just... hang, and then continue playing? I get the latter sometimes. With the HL engine though.

The game doesn't disconnect, in the upper right hand corner the "WARNING:Connection Problem" pops up after about 7 seconds of non-movement then sticks around until I find myself dead on the floor...