Why is performance is slow when 2010 Cassini serves static files?

When running a site in debug mode on 2010 I get incredible slow performance when cassini serves static files. According to Firebug it takes about 1 seconds for each request to resolve on 20 2kb images.

I haven't changed any settings, just have done a stra开发者_运维问答ight up install followed by converting a couple of projects. Rebooted the computer, reloaded IIS without solving anything.

I did have a different problem which I asked about on stackoverflow.com: Exception when VS 2010 ASP.NET Development Server Serves Static Files

Are my problems related?

Any ideas on what could be wrong or should I try a reinstall?

Update: This is not specific to any browser, all of them are just as slow as loading my resources.

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Check out the accepted answer on this question, which is highly relevant if you're using Firefox as your browser:

ASP.NET MVC on Cassini: How can I force the "content" directory to return 304s instead of 200s?