[amibroker] how can I get correct volume information for nasdaq

["cssa_post" <cssa_post@xxxxxxxxx>]

Hi, I use amibroker, and use amiquote to update the database. The 
volume information for nasdaq (^IXIC) was obviously wrong. Some times 
it gives negative numbers, and even the absolute value is different 
from what I get from other website. Do you know how can I get correct 
volume information for the market? Thanks a lot!