fms 3.5 buffering too much

i setup the development versionof  fms 3.5 server on windows 2003 server and it worked great in my tests.  so we bought the server and are putting it in production now.  the only problem is i never "tested" large FLV files.  now if i put a large 50+megabytes flv file in the server it constantly buffers on the client.  Is there  a setting that defines the buffer size to increase the amount of buffer data that gets sent to the client?

if i use a small flv file it works flawlessly but for large files it says "buffering" every 2-5seconds on the client.

the client is just opening the test page that comes with the server the server has 3000mb/s to the internet and the client has a 20mb/s connection so i don't think bandwidth is an issue...