Several factors can cause delay while using proxy server. For example proxy authentication, proxy AV scanning , the bandwidth being assigned to proxy itself or even the DNS etc. Firstly please try pointing to WSA IP instead of FQDN in your browser proxy settings.And then you can create a test Identity and Access Policy in WSA to bypass all add-on features and exclude from proxy authentication. Additionally specific problem description can always help to quickly isolate the issue, for example does this issue happen to all users or specific user? Does this issue happen to all websites or specific website? Only HTTP or HTTPs requests or both of them? How about other browsers, like IE, Firefox etc.
