Slow surfing when is squid enabled

Hi all.

I have setup a squid server for caching.
The problem is, after i have put the URL where i want to go, it takes 13
sec. sometimes even longer to get there. When i disable proxy server setting
in IE, it goes quick, after 2 or 3 sec i can see the page is already
loading.

My config:

cache_dir ufs /var/cache/squid/ 2000 16 256
http_port 10.0.0.10:3128
http_port localhost:3128
#http_port 192.168.1.10:3128
cache_mem 80 MB
hierarchy_stoplist cgi-bin ?
acl QUERY urlpath_regex cgi-bin \?
no_cache deny QUERY
refresh_pattern ^ftp: 1440 20% 10080
refresh_pattern ^gopher: 1440 0% 1440
refresh_pattern . 0 20% 4320
acl all src 0.0.0.0/0.0.0.0
acl edu src 10.0.0.24-10.0.0.250/255.255.255.255
acl manager proto cache_object
acl localhost src 127.0.0.1/255.255.255.255
acl SSL_ports port 443 563
acl Safe_ports port 80
acl Safe_ports port 443 563
acl Safe_ports port 70
acl Safe_ports port 210
acl Safe_ports port 1025-65535
acl Safe_ports port 280
acl Safe_ports port 488
acl Safe_ports port 591
acl Safe_ports port 777
acl CONNECT method CONNECT
http_access allow manager localhost
http_access allow localhost
http_access allow edu
http_access deny manager
http_access deny !Safe_ports
http_access deny CONNECT !SSL_ports
http_access deny all
http_reply_access allow all
icp_port 0
htcp_port 0
dns_nameservers 213.51.129.70 213.51.144.170
#allows to hide the internal ipaddress
forwarded_for off
#dns_testnames 213.51.129.70 213.51.144.170 #tested
with and without
httpd_accel_with_proxy off
httpd_accel_uses_host_header off
httpd_accel_single_host off

What can cause this problem?

Thanx in advance,

Robert