Vpn dropping periodically

Hi,I am having trouble with my vpn connection it drops while running a application and even when not being used but connected.if you wait it will reconnect by itself, a real pain in the neck while working.vpn client is connected to a host pc which is logged into to a domain network through a windows server 2003.a secure gateway through a watchguard firewall,vpn tunnel using safenet soft remote.
If i connect to the server from a client i get no drops.I tested the internet connection by pinging a site with a load and no drops or errors occur.so the internet connection doesn’t seem to be the problem and because the server connection does not have a problem the firewall vpn is ok. I am out of ideas,any help will be appreciated