Another idea: /RESET doesn't have any external circuitry. I haven't looked up the data sheet but I'm guessing some kind internal pullup is inside the FT232R. Unless it has a proper reset circuit in there.

Perhaps it's sensing a reset? A small external cap (0.1uF for a start) and maybe a pullup resistor might help filter the reset line better. 10k and 0.1uF has a time constant of just 1mS so I doubt it will affect the start up when you plug in the USB. It probably wouldn't matter if it was held in reset for a bit initially anyway.