solve lagging problem on my network with QOS
i got a network of 20 computers. Using ADSL from starhub. When some
of the computers are downloading stuff or watching youtube, gaming
will lag. to solve this problem, i bought DIR-655 Xtreme N Gigabit
Router http://www.dlink.com/products/?sec=0&pid=530 and
connnected in this fashion :
starhub modem ==> dlink router ==> hub ==> 20
computers
in my QOS, set maple story as priority 1 ( highest) as shown
here

unforturnately , when downloading at high speeds, other computers
playnig maplestory will lag. ping to yahoo.com is about 1000ms.
does anyone know how to solve this problem?
experts please help