application slow since change to dsl

I am running a wireless bridge to a remote location, and have recently installed a DSL connection in the middle of this wireless bridge connection. Since this connection i have one application that has slowed down to aa crawl at the remote location,at the “wired” Lan side everything is fine, but at the “Wireless” side everything is O.K. but this one application. I have Wingate Proxy running to share the DSL with both sides of the Wireless bridge. Any HELP, or IDEAS would be appreciated.