Server is changing level problem (srcds)

I am searching for an answer for half year. so I geuees i try this forums too…

I downloaded hl2mp with hldsupdatetool and I use cmd to host my own server, but what ever game I try this problem applies for any source game…

If i use changelevel command ,server is changing level, but the loading text “Server is changing level” freezes for clients and they have to hit cancel, and rejoin the server !
It dose change the map, but ingame you have to rejoin, why is it doing this ?!

I tried to join not only from my host PC i tried it from my laptop and people on server confirmed it too.
No firewall, no antivirus.
I deleted all the addons sourcemod, metamod , and just reinstalled my windows 7 32bit

Founded in 2004, Leakfree.org became one of the first online communities dedicated to Valve’s Source engine development. It is more famously known for the formation of Black Mesa: Source under the 'Leakfree Modification Team' handle in September 2004.